在網路看到這題
The surgeon general’s report ______ that smokers create health risks for near
by nonsmokers has encouraged companies to promote smoke-free work environments
.
(A) asserting
(B) asserts
(C) asserted
(D) has asserted
答案是A
想請問為什麼不能選擇B當作
The surgeon general’s report ______ that 的動詞呢