An example of a perfect square is:
Perfect Square:
If a natural number can be expressed as i.e., where is also a natural number, then is called a square number or a perfect square.
For example: can be expressed as and can be expressed as , so and are perfect squares or square numbers.
Since, can be expressed as .
Therefore, is an example of a perfect square.
Explanation for the incorrect options:
Option (B).
Since, cannot be expressed as a square of another natural number, therefore it is not an example of a perfect square.
Option (C).
Since, cannot be expressed as a square of another natural number, therefore it is not an example of a perfect square.
Hence, the correct option is (A) i.e., .