Photosynthetic pigments of Rhodophyceae (red algae) are a. chl a and b b. chl a and c, fucoxanthin c. chl a and d d. chl a,chl d and phycoerythrin.

Options

A. chl a and b
B. chl a and c, fucoxanthin
C. chl a and d
D. chl a,chl d and phycoerythrin.

Explanation

To determine the photosynthetic pigments of Rhodophyceae (red algae), we can analyze the provided options step by step.

### Step 1: Identify the pigments present in Rhodophyceae
Rhodophyceae, commonly known as red algae, have specific photosynthetic pigments. The main pigments include:
- Chlorophyll a
- Chlorophyll d
- Phycoerythrin
- Phycocyanin
- Beta carotene

### Step 2: Analyze the options given
Now, let's evaluate each option based on the pigments identified in Step 1.

- **Option A: Chlorophyll a and b**
- Chlorophyll a is present, but chlorophyll b is not found in Rhodophyceae.
- **Conclusion**: Incorrect.

- **Option B: Chlorophyll a and c, fucoxanthin**
- Chlorophyll a is present, but chlorophyll c and fucoxanthin are not found in Rhodophyceae.
- **Conclusion**: Incorrect.

- **Option C: Chlorophyll a and d**
- Both chlorophyll a and d are present in Rhodophyceae.
- **Conclusion**: This option is partially correct, but it does not include phycoerythrin, which is significant for the red color of these algae.

- **Option D: Chlorophyll a, chlorophyll d, and phycoerythrin**
- This option includes chlorophyll a, chlorophyll d, and phycoerythrin, which are all present in Rhodophyceae.
- **Conclusion**: This is the most appropriate option since it includes the key pigment responsible for the red color.

### Final Answer
The correct answer is **Option D: Chlorophyll a, chlorophyll d, and phycoerythrin**.

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