Numbers like 1,4,9,16,25 are:
A: perfect square
B: non perfect square
C: prime
D: composite

Hint: In these types of questions remember the basic rules of perfect square, non-perfect square, prime number, composite number, and etc. and solve the question.

Complete step-by-step answer:
Let’s first check for the number 1
For perfect square
Since $1 \times 1 = 1$
Therefore 1 is perfect square
But 1 is also a prime number
Since 1 doesn’t have one more divisor other than itself therefore 1 is not a composite.

Now for the number 4
For perfect square
Since $2 \times 2 = 4$
Therefore, 4 is also a perfect square.
Since 4 has more than 2 factors therefore 4 is not a prime number.

For the number 9
For perfect square
Since $3 \times 3 = 9$
Therefore, 9 is a perfect square.

For the number 16
For perfect square
Since $4 \times 4 = 16$
Therefore 16 is a perfect square.

For the number 25
For perfect square
Since $5 \times 5 = 25$
Therefore 25 is also a perfect square.

Since every number is a perfect square therefore the option A is the answer of the question.

Note: In these types of questions check every number for all the options mentioned in the question if all number satisfies any of the options that means the correct option will be the option which is satisfied by every number and also remember if a number satisfies all the options but the next number doesn’t satisfies any 3 options then for the rest of the numbers don’t check the options which is unsatisfied by any number.