GWD31套真题里面的第30套，数学的第9题


Is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
(1)        Two of the interior angles of ABCD are right angles.
(2)         The degree measure of angle ABC is twice the degree measure of angle BCD.
       
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.


我觉得很明显是E,可是答案是C，请高手帮我解释一下吧，谢谢了~~