在他3岁的时候，父亲去世了，母子俩无依无靠，处境更加艰难。

A、At the age of three, he lost his father. With no one to support them, mother and son found life still more difficult.

B、When he was three, his father died; he and his mother were in a difficult situation as there was nobody to support them.

C、At the age of three, he lost his father; he and his mother were in a difficult situation as there was nobody to support them.

D、At the age of three, his father died. With no one to support them, mother and son found life still more difficult.