The term blastocyst is applied to the blastula of which one of the following

Options

A. Kangaroo
B. Platypus
C. Monkey
D. Both kangaroo and monkey

Explanation

To answer the question "The term blastocyst is applied to the blastula of which one of the following?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- The term "blastocyst" refers to a specific stage in embryonic development. It is important to distinguish between the terms "blastula" and "blastocyst" as they are often used interchangeably but refer to different stages in different organisms.

2. **Identifying the Organisms**:
- The question implies that we need to identify which organisms have a blastula stage that is referred to as a blastocyst.

3. **Recognizing the Developmental Stages**:
- In mammals, including humans and monkeys, after fertilization, the zygote undergoes several divisions to form a morula.
- The morula is a solid ball of cells, and as it develops further, a cavity filled with nutritive fluid forms within it. This stage is known as the blastocyst.

4. **Conclusion**:
- Therefore, the term "blastocyst" is specifically applied to the blastula stage of human mammals and monkeys.
- The correct answer to the question is that the blastocyst is found in human mammals and monkeys.

### Final Answer:
The term blastocyst is applied to the blastula of human mammals and monkeys.

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