His parents will be（）him if he fails the examination.

A.disappointing with

B.disappointed on

C.disappointed with

D.disappointing for

铸件各部分的壁厚差异过大时，在厚壁处易产生______缺陷；因冷却速度不一致，在薄壁与厚壁的交界处易产生______缺陷。