Assertion (A): Placental mammals are considered as true mammals.
Reason (R): Only placental mammals feed their young ones with mother's milk.

Options

A. Both A and R are true and R is the correct explanation for A.
B. Both A and R are true but R is not the correct explanation for A.
C. A is true and R is false.
D. A is false and R is true.

Explanation

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Placental mammals are considered as true mammals."
- This statement is accurate because placental mammals (like humans, dogs, and whales) possess all the defining characteristics of mammals, including the presence of mammary glands, hair, and a complex brain structure.

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