---Do you think the last problem in this math test difficult?

---Yes. I could        work it out.

A．hardly

B．easily

C．finally

D．nearly

通过皮肤-直肠反射，促进感觉反馈传入和传出属于直肠训练的（）

A.肌肉的训练

B.直肠感觉的再训练

C.腹部按摩

D.肛门牵张术

E.生物反馈术