Mark the correct statement for Gramineae

Options

A. The carpel has two styles
B. Spikelets are always in pairs
C. Palea is the bracteole
D. Awn is an appendage of the palea

Explanation

### Step-by-Step Solution

1. **Understanding Gramineae**:
- Gramineae, also known as the Poaceae family, includes important cereal crops such as wheat and rice. This family is economically significant and consists entirely of monocotyledons (monocots).

2. **Identifying Key Structures**:
- In Gramineae, the inflorescence is characterized by structures called spikelets. Each spikelet contains flowers that are enclosed by bract-like structures known as palea and lemma.

3. **Defining Palea and Lemma**:
- Palea is a type of bracteol (a modified leaf that supports the flower), while lemma is another bract that is leaf-like. Both structures play a role in supporting the spikelet.

4. **Analyzing the Statements**:
- The question presents several statements about Gramineae. We need to evaluate each one to determine which is correct.
- **Statement 1**: "There are two styles of carpels in Gramineae." - This is incorrect; Gramineae typically has a single superior carpel.
- **Statement 2**: "The spikelets are always in pairs." - This is also incorrect; spikelets can occur singly or in various arrangements.
- **Statement 3**: "Palea is the bracteol." - This is correct; palea is indeed the bracteol of the flower in Gramineae.
- **Statement 4**: "The on is an appendage of palea." - This is incorrect; the on (awn) is an appendage of the lemma, not the palea.

5. **Conclusion**:
- After evaluating all the statements, the correct answer is that "Palea is the bracteol."

### Final Answer
The correct statement for Gramineae is: **Palea is the bracteol.**

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