Assertion (A) : Grasshopper shows male heterogamety.
Reason ( R): In grasshopper, males have one X only XO type).

Options

A. Both assertion (A) and reason ( R) are true and reason ( R) is the correct explanation of assertion (A).
B. Both assertion (A) and reason ( R) are true but reason ( R) is not the correct explanation of assertion (A).
C. Assertion (A) is true but reason ( R) is false.
D. Assertion (A) is false but reason ( R) is true.

Explanation

To solve the question regarding the assertion and reason about grasshopper's male heterogamety, we can break it down into the following steps:

### Step 1: Understand the Terms
- **Assertion (A)**: Grasshopper shows male heterogamety.
- **Reason (R)**: In grasshopper, males have one X only (XO type).

### Step 2: Define Heterogamety
- Heterogamety refers to the presence of two different types of sex chromosomes in an organism. In humans, males have XY chromosomes, while females have XX. In birds, females have ZW and males have ZZ. In insects, such as grasshoppers, males have an XO configuration.

### Step 3: Analyze the Assertion
- The assertion states that grasshoppers exhibit male heterogamety. This is correct because, in grasshoppers, males have one X chromosome and no second sex chromosome (represented as O).

### Step 4: Analyze the Reason
- The reason states that in grasshoppers, males have only one X chromosome (XO type). This is also correct. The "O" indicates the absence of a second sex chromosome, confirming that males are heterogametic.

### Step 5: Conclusion
- Both the assertion and reason are true. Furthermore, the reason correctly explains the assertion, as the XO configuration in grasshoppers is the basis for male heterogamety.

### Final Answer
- Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.

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