列举出战国时期主要的变法代表人物。
魏国李悝、楚国吴起、韩国申不害、齐国邹忌、秦国商鞅。
Tony ________ full marks, but he was so careless as to make a spelling mistake.
A．could have gained
B．can have gained
C．must have gained
D．must gain
