Respuesta :

 tangent is perpendicular to the radius G so 
FG = 4 
FE = 3
GE = 5
so
a^2 + b^2 = 4^2 + 3^2 = 16 + 9 = 25
c^2 = 5^2 = 25
so
c^2 = a^2 + b^2
25 = 25

GFE is a right triangle , <GFE = 90
so FE is perpendicular GF

answer is D.  FE