一个最简真分数,分子与分母的和是7,这样的分数有请选择CBA'x;y'F1m6x4d个。0~3H:H3\/U.l6c1i
A. 10~3H:H3\/U.l6c1i
B.20~3H:H3\/U.l6c1i
C.30~3H:H3\/U.l6c1i