Read the given statements to identify the phytohormone that performs these functions.
(i) Horizontal growth of seedlings, swelling of the axis and apical hook formation in dicot seedlings.
(ii) Promoting senescence and abscission of leaves and flowers.
(iii) Breaking seed and bud dormancy.
(iv) Initiating germination in peanut seeds.
(v) Sprouting of potato tubers.

Options

A. ABA
B. Ethylene
C. GA
D. Cytokinins

Answer

To identify the phytohormone responsible for the functions described in the statements, we will analyze each function step by step.

### Step-by-Step Solution:

1. **Horizontal growth of seedlings, swelling of the axis, and apical hook formation in dicot seedlings**:
- The phytohormone responsible for these functions is **ethylene**. Ethylene promotes horizontal growth and is involved in the formation of the apical hook in dicot seedlings.

2. **Promoting senescence and abscission of leaves and flowers**:
- Ethylene is also known to promote senescence (aging) and abscission (the process of leaves and flowers falling off). This is a key function of ethylene in plants.

3. **Breaking seed and bud dormancy**:
- Ethylene plays a significant role in breaking dormancy in seeds and buds, allowing them to germinate and grow when conditions are favorable.

4. **Initiating germination in peanut seeds**:
- Ethylene is involved in the germination process of various seeds, including peanut seeds, helping to initiate the growth process.

5. **Sprouting of potato tubers**:
- The sprouting of potato tubers is also facilitated by ethylene, which triggers the growth of new shoots from the tubers.

### Conclusion:
Based on the analysis of all the statements, we can conclude that the phytohormone responsible for all the mentioned functions is **ethylene**.

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