John had to start work at an early age his family was very poor.A. orB. soC. butD. becau

问题补充：

John had to start work at an early age, his family was very poor.

A. or

B. so

C. but

D. because

答案：

A. or

B. so

C. but

(答案→)D. because

解析：or或者，是否；so因此；but但是；because因为。句意：约翰不得不很小就开始工作，因为他的家里很穷。故选D。