The key events shown by the telophase is/are
I. Chromosomes cluster at opposite spindle poles and their identity is lost as discrete elements.
II. Nuclear envelope assembles around the chromosome clusters
III. Nucleolus, golgi complex and ER reform

Options

A. I only
B. I and II only
C. II and III only
D. I, II and III

Answer

To solve the question regarding the key events shown by telophase, we will analyze each statement one by one based on our understanding of the telophase stage in mitosis.

### Step-by-Step Solution:

1. **Understanding Telophase**:
- Telophase is the final stage of mitosis, where the separated chromosomes reach opposite poles of the cell.

2. **Analyzing Statement I**:
- **Statement I**: "Chromosomes cluster at opposite spindle poles and their identity is lost as discrete elements."
- In telophase, chromosomes do indeed cluster at opposite spindle poles. However, they do not lose their identity; instead, they begin to de-condense. Thus, this statement is partially correct but misleading. The key point is that they cluster at the poles.

3. **Analyzing Statement II**:
- **Statement II**: "Nuclear envelope assembles around the chromosome clusters."
- This statement is correct. During telophase, the nuclear envelope reforms around each set of chromosomes, creating two distinct nuclei in the daughter cells.

4. **Analyzing Statement III**:
- **Statement III**: "Nucleolus, Golgi complex, and ER reform."
- This statement is also correct. During telophase, the nucleolus reappears, and the Golgi apparatus and endoplasmic reticulum (ER) begin to reform as the cell prepares for cytokinesis.

5. **Conclusion**:
- Based on the analysis, Statements II and III are correct. Statement I is misleading as it suggests that chromosomes lose their identity, which is not entirely accurate. Therefore, the key events shown by telophase are:
- II: Nuclear envelope assembles around the chromosome clusters.
- III: Nucleolus, Golgi complex, and ER reform.

### Final Answer:
The correct answer is that the key events shown by telophase are **II and III**.