Challenge problem of the week

Quantitative comparison:

In the figure, ABC is a right triangle, and PQRS is a square whose area is 396 unit square.

              Quantity A                                                               Quantity B 
The product of the length of AS and the length of RC                  395


(A) Quantity A is greater.
(B) Quantity B is greater.
(C) The two quantities are equal.
(D) The relationship cannot be determined from the information given.

Explanation will be provided !!