GRE Question of the Day (July 22)

Eight points are equally spaced on a circle. If 4 of the 8 points are to be chosen at random, what is the probability that a quadrilateral having the 4 points chosen as vertices will be a square?

A \({\frac{{1}}{{70}}}\)

B \({\frac{{1}}{{35}}}\)

C \({\frac{{1}}{{7}}}\)

D \({\frac{{1}}{{4}}}\)

E \({\frac{{1}}{{2}}}\)