10. Reading magazines and novels ________ helpful.

选 A
Reading magazines and novels 是主语 ,只有一个V-ing(动词ing形式），
如果改为Reading magazines and writing books_____ helpful.就选B.
因为有reading和writing2个动作。

而C,D，都是完成时，直接排除。

选 A
Reading magazines and novels 是主语

b
感觉是
and,,就算是就近 应该也是吧

A
Reading is helpful.
Don't be mislead by the heck "s"

B

A