This project is known to __for three month

题目

This project is known to __for three month
a,having been going on b.go on
c.have been going on d.be going on
选什么为什么?

答案

应该是D
be going on（for）表示：“快到”的意思.这儿不存在完成时态故不需Have.译为：都知道该项目快到三个月了.
例：She must be going on for 18.她准有20岁了.