The discoblastula is found in

Options

A. Echidna
B. Man
C. Branchiostoma
D. Rana

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "DiscoBlastula":**
- The term "discoBlastula" refers to a specific type of blastula that is characterized by a disc-shaped structure. This type of blastula is typically formed in organisms that have a large amount of yolk in their eggs.

2. **Identifying the Organisms in the Options:**
- The options given are echidna, man, brachiostoma, and rena. We need to determine which of these organisms is known to have a discoblastula.

3. **Analyzing Each Option:**
- **Echidna:** This is a monotreme (egg-laying mammal) that has a large yolk in its eggs. It is known to exhibit the formation of a discoblastula.
- **Man:** Humans (and other mammals) typically develop a different type of blastula known as a morula or a blastocyst, which does not fit the description of a discoblastula.
- **Brachiostoma:** This is a type of lancelet, which also does not develop a discoblastula.
- **Rena:** This term is not clearly defined in the context of the question, but if it refers to a type of organism that does not have a significant yolk in its eggs, it would not be associated with a discoblastula.

4. **Conclusion:**
- Based on the analysis, the correct answer is **Echidna**, as it is known to possess a discoblastula due to its egg structure.

**Final Answer:** The discoblastula is found in **Echidna**.

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