In which of the following taxa does photosynthesis not occur ?

Options

A. a) Euglenophyta
B. b) Pyrrophyta
C. c) Rhodophyta
D. d) Sporozoa

Explanation

To determine in which of the following taxa photosynthesis does not occur, we will analyze each option: Euglenophyta, Pyrophyta, Rhodophyta, and Sporozoa.

### Step-by-Step Solution:

1. **Euglenophyta**: This group includes unicellular organisms, many of which are heterotrophic. However, some members, like Euglena, contain chloroplasts and can perform photosynthesis. Therefore, photosynthesis does occur in this taxon.

2. **Pyrophyta**: Also known as dinoflagellates, this group contains organisms that have pigments capable of photosynthesis. Thus, photosynthesis is present in this taxon as well.

3. **Rhodophyta**: Commonly known as red algae, Rhodophyta contains pigments such as phycocyanin that enable them to perform photosynthesis. Therefore, photosynthesis occurs in this taxon too.

4. **Sporozoa**: This group consists of unicellular intracellular parasites, which are known to be heterotrophic and do not possess chloroplasts. They rely on their host for nutrients and do not perform photosynthesis. An example of a sporozoan is Plasmodium, which causes malaria.

### Conclusion:
Based on the analysis, the taxon in which photosynthesis does not occur is **Sporozoa**.

### Final Answer:
**D. Sporozoa**

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