Rationalize the Denominator $c = 25 ( n + 64 ) ^ { 1 / 2 }$

Multiple Choice

Rationalize the denominator. Assume that all variables represent nonnegative numbers and that the denominator is not
zero.
-The cost of manufacturing clocks is given by c $c = 25 ( n + 64 ) ^ { 1 / 2 }$ , where c is the cost in dollars and n is the number produced. What is the cost when no clocks are produced?

A) $1600
B) $25
C) $200
D) $40