Sulphur dioxide causes corrosion by forming sulphuric acid in presence of moisture, damaging iron and steel structures over time. It accelerates rusting and weakens metal integrity, especially in polluted industrial environments.

Hepatitis is a disease that directly affects the liver, causing inflammation. It is usually viral and leads to symptoms like jaundice and fatigue. Other options affect different systems, not specifically the liver.

Crude oil is heated to about 400°C in refineries to vaporize hydrocarbons for fractional distillation. This allows separation into petrol, diesel, and other fractions based on boiling points.

Smooth ER synthesizes lipids such as phospholipids and steroids. It also helps in detoxification. Protein synthesis occurs in rough ER, not smooth ER.

The Paris Climate Conference (COP21) was held in 2015, leading to the Paris Agreement aimed at limiting global warming below 2°C.

Sunspots are dark regions that appear on the surface of the Sun due to intense magnetic activity that lowers the surface temperature in those areas. The first recorded telescopic observation of sunspots is credited to Thomas Harriot, an English astronomer, in 1610. He used an early telescope to observe the Sun and documented these spots before Galileo’s more widely known observations. This discovery challenged the long-standing Aristotelian belief that celestial bodies were perfect and unchanging. The presence of spots on the Sun suggested that it was dynamic and imperfect. Later astronomers such as Galileo Galilei and Christoph Scheiner studied sunspots more extensively and tracked their movement, which helped establish that the Sun rotates on its axis. Albert Einstein is known for the theory of relativity, Isaac Newton for gravity and laws of motion, and René Descartes for contributions to philosophy and mathematics. None of them observed sunspots first. Thus, Thomas Harriot is considered the earliest observer, making option D correct. His work contributed significantly to the development of modern astronomy and our understanding of solar activity.

Benjamin Franklin, a prominent American scientist and statesman, invented both the lightning rod and bifocal spectacles. His lightning rod invention emerged from his experiments with electricity, including the famous kite experiment, which demonstrated that lightning is a form of electrical discharge. The lightning rod protects buildings by directing electrical energy safely into the ground, preventing fires and structural damage. This invention had immediate practical importance and is still widely used today. Franklin also invented bifocal spectacles to address his own vision problems. These glasses combine two lenses in one frame, allowing a person to see both near and distant objects clearly without switching glasses. This was a major convenience and innovation in optics. Other options are notable scientists but unrelated to both inventions: Thomas Edison developed electric devices, Alessandro Volta invented the battery, and Benjamin Banneker was a mathematician and astronomer. Therefore, Benjamin Franklin is the correct answer, as he contributed significantly to both electrical science and practical inventions improving daily life.

The 1935 earthquake struck Quetta, now the capital of Balochistan, Pakistan. It occurred on May 31, 1935, with an estimated magnitude of around 7.7, making it one of the most destructive earthquakes in the region’s history. The earthquake caused massive destruction because most buildings were made of mud and were not designed to withstand seismic activity. It is estimated that between 30,000 and 60,000 people lost their lives. The disaster occurred early in the morning, which increased casualties as people were indoors. Quetta lies in a seismically active zone due to the collision of the Indian and Eurasian tectonic plates. This makes the region highly prone to earthquakes. The 1935 event highlighted the need for earthquake-resistant construction and better disaster preparedness. Other cities like Karachi, Lahore, and Jhelum have not experienced such catastrophic earthquakes historically. Therefore, Quetta is the correct answer. This event remains a key example in studies of seismic hazards and urban vulnerability in South Asia.

The Batura Glacier is located in Gilgit-Baltistan, Pakistan, within the Karakoram mountain range. It is one of the longest glaciers outside the polar regions, stretching approximately 57 kilometers. This glacier is significant because it contributes to the Hunza River, which is part of the Indus River system—Pakistan’s main water source. Glaciers like Batura are crucial for maintaining water supply for agriculture, hydropower, and daily use. Unlike many glaciers worldwide that are retreating due to climate change, some glaciers in the Karakoram region, including Batura, have shown relative stability or even slight growth, a phenomenon known as the “Karakoram anomaly.” Although the Karakoram range extends into China, the Batura Glacier lies within Pakistani territory. Afghanistan and Tibet do not contain this glacier. Thus, Pakistan is the correct answer. Understanding glacier locations is important for geography, environmental science, and water resource management.

The Uch Gas Field is located in Balochistan, Pakistan, and is an important source of natural gas for the country. It was discovered in the mid-20th century and has been developed primarily to supply fuel for power generation. Natural gas from Uch is used in thermal power plants, helping to generate electricity and support industrial activities. This contributes significantly to Pakistan’s energy sector and reduces reliance on imported fuels. Balochistan is rich in natural resources, including gas, coal, and minerals. Other provinces like Sindh also have major gas fields, such as Qadirpur, but Uch specifically belongs to Balochistan. Khyber Pakhtunkhwa and Punjab are not known for the Uch gas field. Therefore, Balochistan is the correct answer. Knowledge of such resources is important for understanding national energy infrastructure and economic geography.