many of those___ in the street said that they would give full support to the decision of the government.

many of those___ in the street 这是主语.
said 谓语
that they would give full support to the decision of the government.这是宾语从句.
所以,可以知道.many of those___ in the street 中间一定是非谓语形式.
AD不对.
many of those___ in the street 主语的意思是,
街上被问到的人,(说他们会全力支持政,府的决议)
被问到,自然是被动,并且已经发生了,所以是B
C这种不定式,是有将来时的意义的,不可以.