The social animal among the options is:

(A) Bee

Explanation:

Bees are known for their highly organized and social behavior. They live in colonies where individuals have specific roles such as workers, drones, and a queen. They communicate with each other, work together for the common good of the colony, and have a complex social structure. In contrast, mosquitoes, bur (assuming it refers to burrowing animals), and domestic flies are not typically considered social animals in the same way as bees. Bees, especially honeybees, are well-known for their intricate social organization and cooperation within the colony.

(A) Guava

Guava is considered one of the richest sources of vitamin C among fruits. It contains a high concentration of ascorbic acid, which is a form of vitamin C. While other fruits like oranges and pineapples also contain vitamin C, guava surpasses them in terms of vitamin C content per serving. Tomatoes, although a good source of vitamin C, are generally lower in vitamin C compared to guava.

(A) Keratin

Hair is primarily composed of a protein called keratin. Keratin is a fibrous structural protein that forms the main component of hair, as well as nails and the outer layer of the skin. It provides strength and resilience to these structures. The other options—Casein, Globulin, and Mucin—are proteins found in other parts of the body and have different functions.

Answer: A) Chloroplasts Explanation: Chloroplasts contains chlorophyll, the green substance in plants that allows them to create food from carbon dioxide and water called as photosynthesis.