The leaves of a plant combine a gas A taken from air and a liquid B taken from the soil in the presence of sunlight to make a simple food C by the process called D. some of the simple food C gets converted into a complex food E which is stored in the various parts of the plant including its leaves
Which of the two foods, C or E, will give blue-black colour with dilute iodine solution ?

Answer

### Step-by-Step Solution:

1. **Identify the Process**: The leaves of a plant combine a gas (A) from the air and a liquid (B) from the soil in the presence of sunlight. This process is known as **photosynthesis** (D).

2. **Identify the Components**:
- Gas A: **Carbon dioxide (CO₂)** from the air.
- Liquid B: **Water (H₂O)** from the soil.

3. **Identify the Simple Food (C)**: The simple food produced during photosynthesis is **glucose** (C), which is a simple carbohydrate.

4. **Identify the Complex Food (E)**: Some of the glucose (C) produced is converted into a complex carbohydrate known as **starch** (E). Starch serves as a storage form of food in plants.

5. **Perform the Iodine Test**: To determine which food gives a blue-black color with dilute iodine solution:
- The iodine test is used to check for the presence of starch. When iodine is added to starch, it turns blue-black.
- Glucose does not give a blue-black color with iodine.

6. **Conclusion**: The complex food (E), which is starch, will give a blue-black color with dilute iodine solution.

### Final Answer:
The food that will give a blue-black color with dilute iodine solution is **E (starch)**.

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