Antiauxin used in picking cotton balls is

Options

A. 2, 4-D
B. TIBA
C. NAA
D. Both A and B.

Answer

To solve the question regarding the antiauxin used in picking cotton balls, we will analyze the options provided and determine which one is correct.

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the antiauxin used in the process of picking cotton balls. Antiauxins are substances that inhibit the effects of auxins, which are plant hormones that promote growth.

2. **Review the Options**: The options given are:
- 1. 2,4-D (2,4-Dichlorophenoxyacetic acid)
- 2. TIBA (Tridobenzoic acid)
- 3. NAA (Naphthalene acetic acid)
- 4. Both A and B

3. **Analyze Option 1 (2,4-D)**:
- 2,4-D is a synthetic auxin, not an antiauxin. It is primarily used as a herbicide and promotes plant growth rather than inhibiting it. Therefore, this option is incorrect.

4. **Analyze Option 2 (TIBA)**:
- TIBA, or Tridobenzoic acid, is known to act as an antiauxin. It is used in the agricultural practice of defoliation, which helps in the mechanical harvesting of cotton by making it easier to pick the cotton balls. This option appears to be correct.

5. **Analyze Option 3 (NAA)**:
- NAA is another type of auxin, specifically Naphthalene acetic acid. Like 2,4-D, it promotes growth and is not an antiauxin. Thus, this option is also incorrect.

6. **Analyze Option 4 (Both A and B)**:
- Since option 1 (2,4-D) is incorrect, option 4 cannot be correct either.

7. **Conclusion**: Based on the analysis, the correct answer to the question is option 2, TIBA (Tridobenzoic acid), as it is the antiauxin used in picking cotton balls.

### Final Answer:
The antiauxin used in picking cotton balls is **TIBA (Tridobenzoic acid)**.

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