The cut flowers and vegetables can be kept fresh for a long period with the help of:

Options

A. Cytokinin
B. Ethylene
C. Auxin
D. Gibberellin

Answer

To solve the question about which hormone helps keep cut flowers and vegetables fresh for a long period, we can analyze the functions of the given options: cytokinin, ethylene, auxin, and zyberlin.

### Step-by-Step Solution:

1. **Understand the Role of Cytokinin**:
- Cytokinins are plant hormones that promote cell division and growth. They help delay the aging process (senescence) in plants by mobilizing nutrients and promoting the growth of new tissues.

2. **Analyze Ethylene**:
- Ethylene is a gaseous plant hormone that is primarily involved in the ripening of fruits. It accelerates the ripening process, which is not desirable for keeping cut flowers and vegetables fresh for a longer time.

3. **Consider Auxin**:
- Auxins are hormones that regulate various aspects of plant growth, including apical dominance and the differentiation of xylem. However, they are not specifically known for prolonging freshness in cut flowers and vegetables.

4. **Review Zyberlin**:
- Zyberlin (also known as gibberellin) is involved in promoting stem elongation, seed germination, and other growth processes. It does not play a significant role in delaying senescence.

5. **Conclusion**:
- Among the options provided, cytokinin is the hormone that effectively delays senescence and helps keep cut flowers and vegetables fresh for a longer period. Therefore, the correct answer is **cytokinin**.

### Final Answer:
The cut flowers and vegetables can be kept fresh for a long period with the help of **cytokinin**.