The auxin commonly used in promoting rootings of cuttings is

Options

A. NAAM
B. IBA
C. NAA
D. Both B and C.

Answer

**Step-by-Step Solution:**

1. **Understanding Auxins**: Auxins are a class of plant hormones that play a crucial role in the growth and development of plants. They are involved in various processes including cell elongation, root formation, and fruit development.

2. **Identifying the Auxins**: The question provides four options:
- A) NAA (Naphthalene Acetic Acid)
- B) IBA (Indole-3-butyric Acid)
- C) NAA (Naphthalene Acetic Acid)
- D) Both B and C

3. **Researching the Auxins**:
- NAA is a synthetic auxin that is known for its effectiveness in promoting root formation in plant cuttings.
- IBA is also an auxin that is commonly used for rooting but is not mentioned as the most common in this context.
- The option "Both B and C" suggests that both IBA and NAA are used, but the question asks for the commonly used one.

4. **Conclusion**: Based on the information, NAA is specifically highlighted as a synthetic auxin that promotes rooting effectively in cuttings. Therefore, the correct answer to the question is **C) NAA**.

**Final Answer**: C) NAA

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