The height of a triangle is 4 inches greater than twice its base. The area of the triangle is no more than 168 in.² which inequality can be used to find the possible lengths, x, of the base of the triangle?
A. x(x+2)=>168
B. x(x+2)=<168
C. 1/2x(x+4)=<168
D. 1/2x(x+4)=>168