— May I speak to Jim Green?
— _________ He is in the supermarket now.
A:Who are you speaking?
B:Yes, of course you can.
C:Could you call him later?
D:This is Jim Green.
下列关于长颈鹿长颈性状形成原因原描述,符合达尔文自然选择学说的是( )
你同意他们的说法吗?请说明你的理由。
12:13= ____ (填带分数)