Minimize $S = x + y$ With $x y = 25$ And Both

Multiple Choice

Minimize $S = x + y$ with $x y = 25$ and both $\chi$ and $y > 0$ .

A) $S = - 15$
B) $S = 10$
C) $S = 25$
D) $S = 8$
E) $S = 5$