$A=f(s)=s^{2}$ Is the Area of a Square of Side Length $s$

Multiple Choice

$A=f(s) =s^{2}$ is the area of a square of side length $s$ . What does $f(36)$ mean in terms of the square?

A) $f(36) =1296$ , the area of a square of side length 36 .
B) $f(36) =6$ , the area of a square of side length 6 .
C) $f(36) =1296$ , the area of a square of side length 1296 .
D) $f(36) =6$ , the area of a square of side length 6 .