A phylum in which the digestion is intracellular as well as extracellular and polyp body form is seen includes organisms which:

Options

A. Are triploblastic.
B. Show internal fertilization and indirect development.
C. Have special cells called choanocytes.
D. Have a central gastro-vascular cavity with a single opening.

Answer

To solve the question regarding the phylum that exhibits both intracellular and extracellular digestion and has a polyp body form, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Characteristics of the Phylum**:
- The question specifies that the organisms have both intracellular and extracellular digestion. This suggests a phylum that has a complex digestive system.
- The presence of a polyp body form indicates that we are looking for organisms that can exist in a sessile form, which is characteristic of certain aquatic organisms.

2. **Consider the Relevant Phyla**:
- The phylum Cnidaria (formerly known as Silantrata) includes organisms like jellyfish, corals, and sea anemones. This phylum is known for having both polyp and medusa forms.
- Cnidarians have a gastrovascular cavity where digestion occurs, which allows for both intracellular digestion (within cells) and extracellular digestion (in the cavity).

3. **Evaluate the Characteristics of Cnidaria**:
- Cnidarians are diploblastic, meaning they have two germ layers (ectoderm and endoderm).
- They possess specialized cells called cnidocytes, which are used for defense and capturing prey.
- They exhibit radial symmetry and typically reproduce through external fertilization.

4. **Analyze the Options Given**:
- The question implies that we need to find the correct statement about the organisms in this phylum.
- The correct characteristic is that they have a central gastrovascular cavity with a single opening, which is true for Cnidaria.

5. **Conclusion**:
- Based on the analysis, the correct answer to the question is that the phylum in which digestion is both intracellular and extracellular and where the polyp body form is seen includes organisms from the phylum Cnidaria.

### Final Answer:
The correct phylum is **Cnidaria**.

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