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.

Red blood cells (RBCs), also known as erythrocytes, have an average lifespan of about 120 days in the human body. They are responsible for transporting oxygen from the lungs to tissues and carrying carbon dioxide back to the lungs for exhalation. RBCs lack a nucleus and most organelles, which allows more space for hemoglobin but limits their ability to repair themselves. Over time, they become less flexible and are eventually removed from circulation by the spleen and liver. The body continuously produces new RBCs in the bone marrow to replace the old ones. This balance ensures a stable supply of oxygen to tissues. Other options such as 45, 125, and 145 days are incorrect as they do not match the established average lifespan. Thus, 120 days is the correct answer. This concept is important in understanding blood physiology, anemia, and overall human health.

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.

A parsec is a unit of distance used in astronomy. It is defined as the distance at which one astronomical unit subtends an angle of one arcsecond. One parsec is approximately equal to 3.26 light-years. It is commonly used to measure distances between stars and galaxies because these distances are extremely large. Speed, time, and acceleration are different physical quantities and do not apply here. Therefore, distance is the correct answer. Parsec is especially useful in parallax measurements, where astronomers calculate distances based on the apparent shift of a star’s position.

Ethiopia experienced a severe famine during 1983–1985, which became one of the most well-known humanitarian crises of the 20th century. It was caused by a combination of drought, political instability, and poor agricultural policies. The famine led to widespread starvation and the deaths of hundreds of thousands of people. It also triggered global humanitarian efforts, including aid campaigns and awareness programs. This event highlighted the importance of food security, disaster management, and international cooperation in addressing crises. Other periods listed are incorrect for this major famine. Thus, 1983–1985 is the correct answer, representing a significant historical event in global humanitarian efforts.