My early_______ at learning playing the piano was a failure although I took a fancy to it.

A．attempt

B．effort

C．assumption

D．intention

关于甲状腺肿的临床症状，下列说法正确的是（）

A.一般无明显症状

B.多出现甲亢的症状

C.多出现甲低的症状

D.重度肿大时可出现气促、吞咽困难或声音嘶哑等压迫症状

E.胸骨后甲状腺肿可使头部、颈部和上肢静脉回流受阻