The most common cytokinin is

Options

A. Isopentanyle adenine
B. Kinetin
C. Dihydrozeatin
D. IPA.

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the most common cytokinin among the given options: pentanyl adenine, kinetin, dihydrozeatin, or IPA.

2. **Define Cytokinins**: Cytokinins are a class of plant hormones that play a crucial role in promoting cell division (cytokinesis) in plant roots and shoots. They are essential for plant growth and development.

3. **Identify Types of Cytokinins**: Cytokinins can be classified into two main categories: isoprenoid and aromatic cytokinins.

4. **Identify the Most Common Cytokinin**: Among the isoprenoid cytokinins, isopentanyl adenine is the most abundantly found in plants.

5. **Select the Correct Answer**: Based on the information provided, the most common cytokinin from the options given is **isopentanyl adenine**.

**Final Answer**: The most common cytokinin is **isopentanyl adenine**.

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