Science

Digestion of food is completed in the small intestine where enzymes break down nutrients fully for absorption. The stomach initiates digestion, and the large intestine mainly absorbs water and forms feces.

The Great Red Spot is a giant storm located on the planet Jupiter. It is a well-known and long-lasting feature of Jupiter's atmosphere, making option B the correct answer.

Vitamin D deficiency leads to rickets, a condition characterized by weak or soft bones in children due to impaired calcium absorption. Scurvy is caused by vitamin C deficiency, and hair fall is not directly linked to vitamin D deficiency.

The macula is the most sensitive part of the eye responsible for sharp, central vision, making it the most sensitive layer compared to the cornea or pupil.

A lactometer is an instrument used to measure the purity or density of milk. It helps determine if milk has been adulterated with water or other substances. Therefore, the purity measured by a lactometer is that of milk.

Leather is primarily composed of collagen, a structural protein found in animal skin. Collagen provides the strength and flexibility characteristic of leather.

Venus has the slowest rotation period of all the planets in the solar system, taking about 243 Earth days to complete one rotation, which is slower than Mars, Jupiter, or any other planet.

Mercury is the only metallic element that is liquid at room temperature. Since it is not listed among the options, the correct choice is 'None of these.'

Vitamin K is the vitamin responsible for blood clotting, and since it is not listed among the options, the correct choice is 'None of these.' Vitamins A, D, and C do not play a direct role in blood clotting.

Synthetic vinegar is primarily composed of acetic acid, which is the chemical responsible for vinegar's characteristic smell and taste. Therefore, the chemical name of synthetic vinegar is acetic acid.