PGR which induces the formation of new leaves and chloroplast in leaves is

Options

A. Cytokinins
B. Ethylene
C. Gibberellins
D. Abscisic acid

Answer

To solve the question regarding which plant growth regulator (PGR) induces the formation of new leaves and chloroplasts in leaves, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding PGRs**:
- Begin by defining what PGRs are. PGR stands for Plant Growth Regulators, which are chemical substances that influence plant growth and development.

2. **Identifying the Options**:
- The options given are cytokinins, ethylene, gibberellins, and abscisic acid. We need to evaluate each of these to determine which one is responsible for the formation of new leaves and chloroplasts.

3. **Analyzing Cytokinins**:
- Cytokinins are a group of plant hormones that promote cell division (mitosis) in plants. They are known to stimulate the growth of new leaves and the formation of chloroplasts in those leaves.

4. **Evaluating Ethylene**:
- Ethylene is a plant hormone that is primarily involved in processes such as fruit ripening, flower opening, and transverse growth. It does not play a significant role in the formation of new leaves or chloroplasts.

5. **Considering Gibberellins**:
- Gibberellins are hormones that promote seed germination and flowering. They do not induce the formation of new leaves or chloroplasts.

6. **Reviewing Abscisic Acid**:
- Abscisic acid is known as a growth inhibitor. It generally inhibits growth and does not promote the formation of new leaves or chloroplasts.

7. **Conclusion**:
- Based on the analysis, the correct answer is **cytokinins**, as they are the PGRs that induce the formation of new leaves and chloroplasts.

### Final Answer:
The PGR which induces the formation of new leaves and chloroplasts in leaves is **cytokinins**.