A: The ovoviviparous organisms give birth to young ones.
R: The eggs are incubated within the uterus and receive nourishment from the placenta during development .

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion
B. It both Assertion & Reason are true but the reason is not the correct explanation of the assertion
C. If Assertion is true statement but Reason is false
D. If both Assertion and Reason are false statements

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "ovoviviparous organisms give birth to young ones."
- This means that these organisms do not lay eggs that develop outside their body; instead, the eggs develop inside the mother's body and hatch there.

2. **Understanding the Reason (R)**:
- The reason states that "the eggs are incubated within the uterus and receive nourishment from the placenta during development."
- This indicates that during the development of the young ones, they are supported by the mother's body, specifically through the placenta, which is a structure that provides nutrients and oxygen to the developing embryos.

3. **Classification of Organisms**:
- Organisms can be classified into three categories based on their reproductive methods:
- **Oviparous**: These organisms lay eggs (e.g., birds, most reptiles).
- **Viviparous**: These organisms give birth to live young (e.g., mammals).
- **Ovoviviparous**: These organisms have eggs that hatch inside the mother's body, and the young are born live (e.g., some species of sharks and snakes).

4. **Evaluating the Truth of the Statements**:
- The assertion is true because ovoviviparous organisms do indeed give birth to live young.
- The reason is also true because it accurately describes the process of development in ovoviviparous organisms, where eggs are incubated within the body and receive nourishment.

5. **Conclusion**:
- Both the assertion and the reason are true statements.
- The reason provides a correct explanation for the assertion, confirming that the process described is how ovoviviparous organisms give birth to young ones.

### Final Answer:
Both the assertion (A) and the reason (R) are true, and the reason correctly explains the assertion.

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