Explanation:

- Option 1: Sugar

- Sugar is a compound made of carbon, hydrogen, and oxygen atoms bonded chemically.

- Common table sugar is known as sucrose (C12H22O11).

- Option 2: Air

- Air is a mixture of different gases like nitrogen, oxygen, carbon dioxide, and others.

- Since it's a mixture, not a chemically bonded substance, it's not a compound.

- Option 3: Milk

- Milk is a colloidal solution and mixture of water, fats, proteins, and lactose.

- It's not a single compound but rather a complex mixture.

- Option 4: Tea

- Tea is a mixture of water, tea compounds, and other additives.

- Similar to milk, it's not a single chemical compound.

Correct Answer: Option 1 - Sugar