Stop cutting trees, _______ the earth will become worse and worse.

A．and

B．then

C．because

D．or

甲状腺大部切除术后，呼吸困难和窒息的并发症与下列哪项因素无关

A．气管软化塌陷

B．喉返神经损伤两侧声带麻痹

C．喉头水肿

D．手术创伤的应激诱发危象

E．切口内出血压迫气管