You won’t feel happy at school ___ you get on well with your classmates.

A．though

B．when

C．unless

D．because

瓜藤缠相当于西医学的( )

A．结节性红斑

B．硬结性红斑

C．持久性隆起性红斑

D．皮肤变应性血管炎

E．多形性红斑