There is no power like power of confidence, and there is no student as competitive as st

There is no power like power of confidence, and there is no student as competitive as student who trusts his own abilities.
A. the; a
B. a; the
C. /; a
D. the; /

(答案→)A. the; a B. a; the C. /; a D. the; /解析：根据句意：没有哪种力量能像自信的力量，同样也没有哪个学生能比相信他自己能力的学生有竞争力。第一空中特指的是自信的力量，所以要用定冠词the;第二空中a表泛指，尽管有定语从句修饰，但并不能用the,这里a student,表示一类学生，故选A.

就是这个解释