One of the commonly used plant growth hormone is pineapple to promote flowering is
(a) ethylene
(b) abscisic acid
(c) zeatin
(d) indole-3-acetic acid

Options

A. ethylene
B. abscisic acid
C. zeatin
D. indole-3-acetic acid

Answer

To solve the question regarding which plant growth hormone is commonly used in pineapples to promote flowering, we will analyze each of the options provided:

1. **Understanding the Options**:
- **(a) Ethylene**: This is a gaseous plant hormone primarily involved in the process of fruit ripening. While it does play a role in various plant processes, its main function is not to promote flowering.
- **(b) Abscisic Acid (ABA)**: This hormone is known as a stress hormone. It is produced in response to stress conditions (like drought) and does not promote flowering.
- **(c) Zeatin**: This is a type of cytokinin, which is involved in cell division and growth but is not directly associated with the promotion of flowering.
- **(d) Indole-3-acetic Acid (IAA)**: This is a type of auxin, which is known to promote flowering in certain plants, including pineapples. Auxins help in the transition of vegetative buds to floral buds.

2. **Elimination of Incorrect Options**:
- Ethylene does not promote flowering; it is more related to fruit ripening.
- Abscisic acid is not involved in flowering but rather in stress responses.
- Zeatin, while important for growth, does not specifically induce flowering.

3. **Identifying the Correct Answer**:
- The only option left that is known to promote flowering in pineapples is **Indole-3-acetic Acid (IAA)**. Auxins like IAA are crucial in the flowering process as they help convert vegetative buds into floral buds.

Thus, the correct answer is **(d) Indole-3-acetic acid**.