Question

In the figure above , OACB is a square with area 4x^2. If OA and OB are radii of a sector of a circle O, what is the perimeter, in terms of x, of the unbroken figure?

A) x(4+3 π)
B) x(3+4pi)
C) x(6+4 π)
D) 4(x+2 π)
E) 7 πx