Look, it's so amazing! The wings of the model plane made by the boy are ____ of its body.  [      ]

A. more than the length twice    

B. twice more than the length

C. more than twice the length      

D. more twice than the length

在蛋白质消化中起外肽酶作用的是

A．胰蛋白酶
B．糜蛋白酶
C．弹性蛋白酶
D．胃蛋白酶
E．氨基肽酶