Question

PLEASE HELP
http://usatestprep.com/modules/gallery/files/61/6140/6140.gif

Which quadrilateral can be inscribed in a circle?
A)
B)
C)
D)

Answer 1

i picked D cuz thats the one that makes the most sense

Answer 2

A convex quadrilateral ABCD is cyclic if and only if its opposite angles are supplementary, that is
\[
A + C = B + D = \pi = 180^{\circ}.
\]

http://en.wikipedia.org/wiki/Cyclic_quadrilateral#Characterizations