A: Mitosis is a equational division .
R:During mitosis the number of chromosomes is reduced to a half.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To analyze the assertion and reason provided in the question, we will break down each statement step by step.

### Step 1: Understanding the Assertion
**Assertion (A): Mitosis is an equational division.**
- Mitosis is indeed referred to as an equational division because it results in two daughter cells that are genetically identical to the parent cell.
- During mitosis, the number of chromosomes and the amount of DNA in the daughter cells remains the same as in the parent cell.
- For example, if a diploid cell (2n) with 46 chromosomes undergoes mitosis, it will produce two daughter cells, each also with 46 chromosomes.

### Step 2: Understanding the Reason
**Reason (R): During mitosis, the number of chromosomes is reduced to half.**
- This statement is incorrect. In mitosis, the chromosome number does not get reduced. Instead, it remains constant.
- The process that reduces the chromosome number by half occurs during meiosis, not mitosis. In meiosis, a diploid cell divides to form haploid cells, resulting in half the number of chromosomes.

### Step 3: Conclusion
- Since the assertion (A) is true and the reason (R) is false, we conclude that the correct relationship is that A is true, and R is false.

### Final Answer
- Therefore, the correct answer to the question is that the assertion is true, and the reason is false.

---