A : Mendel gave postulates like "principles of segregation and principles of independent assortment" after studying seven pairs of contrasting traits in garden pea.
R : He was lucky in selecting seven characters in pea that were located on seven different chromosomes.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion , then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To analyze the assertion (A) and reason (R) provided in the question, we will break down the statements and evaluate their validity step by step.

### Step 1: Understanding the Assertion (A)
The assertion states that "Mendel gave postulates like the principles of segregation and independent assortment after studying seven pairs of contrasting traits in garden pea."

**Analysis**:
- Gregor Mendel is indeed known for formulating the principles of segregation and independent assortment based on his experiments with garden peas (Pisum sativum).
- He studied seven pairs of contrasting traits, such as seed shape, seed color, flower shape, etc.

**Conclusion**: The assertion is **true**.

### Step 2: Understanding the Reason (R)
The reason states that "He was lucky in selecting seven characters in pea that were located on seven different chromosomes."

**Analysis**:
- While Mendel did select seven contrasting traits, these traits are not located on seven different chromosomes. In fact, they are located on only four different chromosomes.
- For example, some traits are linked on the same chromosome, which contradicts the statement that each trait is on a separate chromosome.

**Conclusion**: The reason is **false**.

### Step 3: Final Evaluation
Now, we combine our conclusions from the assertion and reason:
- Assertion (A) is **true**.
- Reason (R) is **false**.

Thus, the correct answer to the question is that the assertion is true, but the reason is false.

### Summary of the Solution
- Assertion (A) is true: Mendel formulated principles based on seven pairs of traits.
- Reason (R) is false: The traits were not on seven different chromosomes.