The climate conference was attended by 11 000 people it the largest UN gathering ever hel

问题补充：

The climate conference was attended by 11,000 people, it the largest UN gathering ever held.

A. making

B. to make

C. made

D. to be making

答案：

(答案→)A. making

B. to make

C. made

D. to be making

解析：考查非谓语动词作结果状语。To do 变出人意料的结果；doing表自然而然的结果。句意：气候大会有11,000人参加，从而使它成为曾经举行的最大的联合国会议。表自然而然的结果，所以选A。