Rainfall is measured using a rain gauge, a meteorological instrument designed to collect and measure precipitation. It typically consists of a funnel that directs rainwater into a measuring cylinder. The amount of rainfall is recorded in millimeters, representing the depth of water that would accumulate on a flat surface. Accurate rainfall data is essential for agriculture, flood prediction, and weather forecasting. A hydrometer measures liquid density, not rainfall. “Rain meter” and “hydroscope” are not standard instruments. Thus, rain gauge is the correct answer. It is widely used by meteorological departments worldwide.

Amjad Hussain Sial from Pakistan served as the Secretary-General of SAARC (South Asian Association for Regional Cooperation). SAARC is a regional organization that promotes economic and cultural cooperation among South Asian countries. The Secretary-General is responsible for coordinating activities, implementing decisions, and facilitating cooperation among member states. The position rotates among member countries. Antonio Guterres is the UN Secretary-General, not SAARC. Ajay Bisaria is an Indian diplomat, and Arjun Bahadur Thapa is a former SAARC Secretary-General. Thus, Amjad Hussain Sial is the correct answer in this context, reflecting leadership within regional cooperation frameworks.

Kirthar range spans Sindh and Balochistan, so both A & B correct.

Vitamin D is essential for calcium absorption and bone health. Its deficiency leads to rickets in children, a condition characterized by soft and weak bones, leading to deformities such as bowed legs. In adults, vitamin D deficiency can cause osteomalacia, which results in bone pain and muscle weakness. Vitamin D is obtained from sunlight exposure and certain foods. Scurvy is caused by vitamin C deficiency, and night blindness is due to vitamin A deficiency. Fibrosis is unrelated. Thus, rickets is the correct answer. This highlights the importance of balanced nutrition and sunlight exposure for maintaining healthy bones.

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.