我们要团结带领各界人士齐心协力谋发展、促和谐。

A.We must unite and lead the people of all sectors in an active and concerted effort to promote development and harmony.

B.We must suggest and lead the people of all sectors in an active and concerted effort to promote development and harmony.

C.We must unite and lead the people of all sectors in an active and concerted effort to promote development and prosperity.

正确答案：We must unite and lead the people of all sectors in an active and concerted effort to promote development and harmony.