The famouse writer Lin Qingxuan ______to come to our school to give a speech again.

A．possible

B．likely

C．probable

D．perhaps

C₃位羟基结合型的甾体化合物能被碱水解的多数属于（ ）

A．强心苷类

B．甾体皂苷类

C．蟾毒类

D．甾醇苷类

E．蜕皮激素类