Diplotene phase of meiosis is also charactertised by
a. Desynapsis
b.Complete terminalisation of chiasmata
c.Dictyotene stage
d. Complete disappearance of nuclear membrane and nucleoli
e. Complete development of astral rays and aster
f. Longest phase of prophase-I

Options

A. a, b, c, and e
B. b, d, e, and f
C. a, c, and f
D. b, d, and f

Answer

To solve the question regarding the characteristics of the Diplotene phase of meiosis, let's analyze each option step by step.

### Step 1: Understanding Diplotene Phase
The Diplotene phase is a part of prophase I in meiosis. During this phase, homologous chromosomes begin to separate but remain attached at points called chiasmata, where crossing over has occurred.

### Step 2: Evaluating Each Option
- **a. Desynapsis**: This refers to the separation of homologous chromosomes which occurs during the Diplotene phase. This is a correct characteristic.

- **b. Complete terminalisation of chiasmata**: While terminalisation of chiasmata begins in the Diplotene phase, it is not completed until the next stage, Diakinesis. Therefore, this is not a characteristic of the Diplotene phase.

- **c. Dictyotene stage**: The Dictyotene stage is a prolonged arrest of the Diplotene phase, particularly in oocytes. This is a correct characteristic as it describes a state within the Diplotene phase.

- **d. Complete disappearance of nuclear membrane and nucleoli**: This occurs in the later stages of meiosis, specifically in Diakinesis, not in Diplotene. Thus, this is incorrect.

- **e. Complete development of astral rays and aster**: This is not characteristic of the Diplotene phase. Astral rays and aster formation are more relevant to the later stages of cell division.

- **f. Longest phase of prophase-I**: The Diplotene phase is indeed one of the longest phases of prophase I, as it can last for a significant amount of time, especially in oocytes. This is a correct characteristic.

### Conclusion
Based on the analysis, the characteristics of the Diplotene phase include:
- Desynapsis (a)
- Dictyotene stage (c)
- Longest phase of prophase-I (f)

Thus, the correct answer is **a, c, and f**.

### Final Answer
The Diplotene phase of meiosis is characterized by:
- a. Desynapsis
- c. Dictyotene stage
- f. Longest phase of prophase-I