Go through the following statements -
I. Promotes flowering in pineapple
II. Used to prepare weed free lawn
III. Promotes the abscission of older mature leaves and fruits The above functions are carried out by

Options

A. GA
B. `C_2 H_4`
C. ABA
D. Auxin

Answer

To solve the question regarding the functions carried out by certain plant hormones, we will analyze each statement and identify the correct hormone responsible for each function.

### Step-by-Step Solution:

1. **Analyzing Statement I: "Promotes flowering in pineapple."**
- The hormone responsible for promoting flowering in pineapple is **auxin**. Auxins are known to stimulate flowering in certain plants, including pineapple.

2. **Analyzing Statement II: "Used to prepare weed-free lawn."**
- The hormone used to prepare weed-free lawns is also **auxin**. Synthetic auxins are commonly used as herbicides to eliminate dicot weeds while leaving monocots (like grasses) unharmed.

3. **Analyzing Statement III: "Promotes the abscission of older mature leaves and fruits."**
- The hormone responsible for promoting abscission (the process of shedding leaves and fruits) is **ethylene**. Ethylene is a gaseous plant hormone that plays a key role in the abscission process.

### Conclusion:
From the analysis, we can conclude that:
- Statement I is associated with **auxin**.
- Statement II is associated with **auxin**.
- Statement III is associated with **ethylene**.

Thus, the functions described in the statements are primarily carried out by **auxin** and **ethylene**.

### Final Answer:
The above functions are carried out by **auxin** (for statements I and II) and **ethylene** (for statement III).

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