选择题
2008 AMC 8 Problem 19: Points Around a Square
Eight points are spaced around at intervals of one unit around a 2 × 2 square, as shown. Two of the 8 points are chosen at random. What is the probability that the two points are one unit apart?
A.
1/4
B.
2/7
C.
4/11
D.
1/2
E.
4/7