When bitten by ant, the sting causes irritation due to the presence of

Options

A. a base in the sting
B. formic acid in the sting
C. poisonous chemicals
D. both (a) and (b)

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why irritation occurs when bitten by an ant. This irritation is caused by a substance present in the ant's sting.

2. **Identifying the Substance**: When an ant bites, it injects a substance through its sting. The primary substance responsible for the irritation is an acid.

3. **Recognizing the Acid**: The specific acid that causes irritation from an ant sting is known as formic acid.

4. **Chemical Formula**: The molecular formula of formic acid is HCOOH. It is also referred to as methanoic acid in chemical nomenclature.

5. **Effect of the Acid**: The irritation occurs because formic acid is a weak acid that can cause a burning sensation and discomfort on the skin.

6. **Neutralizing the Effect**: To alleviate the irritation caused by formic acid, a mild base can be applied. An example of a mild base is baking soda (sodium bicarbonate, NaHCO3), which can neutralize the acid.

7. **Conclusion**: Therefore, the irritation from an ant sting is due to the presence of formic acid.

### Final Answer:
The irritation caused by an ant sting is due to the presence of formic acid.

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