A student observed an algae with chlorophyll 'a', 'd' and phycoerythrin. It should belong to:

Options

A. Phaeophyta
B. Rhodophyta
C. Chlorophyta
D. Bacillariophyta

Answer

To determine the classification of the algae observed by the student, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Pigments Present**: The student observed an algae that contains chlorophyll 'a', 'd', and phycoerythrin.

2. **Understand the Types of Algae**: Algae are classified into several groups based on their pigments:
- **Chlorophyta (Green Algae)**: Contains chlorophyll 'a' and 'b'.
- **Rhodophyta (Red Algae)**: Contains chlorophyll 'a', 'd', and phycoerythrin.
- **Phaeophyta (Brown Algae)**: Contains chlorophyll 'a' and 'c'.
- **Bacillariophyta (Diatoms)**: These are not classified as algae in this context.

3. **Analyze the Pigments Against Algal Groups**:
- Since the algae has chlorophyll 'a' and 'd', it cannot belong to Chlorophyta (which has 'a' and 'b') or Phaeophyta (which has 'a' and 'c').
- The presence of phycoerythrin is a characteristic feature of Rhodophyta.

4. **Conclusion**: Based on the presence of chlorophyll 'a', 'd', and phycoerythrin, the algae must belong to the group **Rhodophyta**.

### Final Answer:
The algae should belong to **Rhodophyta** (Red Algae).

---