The original building and loan associations were organized as limited life funds, whose members made monthly payments on their share subscriptions, then taking turns drawing on the funds for home mortgages.

(A) subscriptions, then taking turns drawing

(B) subscriptions, and then taking turns drawing

(C) subscriptions and then took turns drawing

(D) subscriptions and then took turns, they drew

(E) subscriptions and then drew, taking turns

今天再看了一次這題,還是不是很清楚,哪一位nn好心幫我解釋一下

還有drawing這裡用Ving的形式,是為什麼呢???