One Reason Why European Population Grew Slowly or Not at All

One reason why European population grew slowly or not at all in the seventeenth century was because

A) only three in four children reached adulthood.
B) tens of thousands were emigrating to the New World.
C) couples tended to marry young, then find themselves unable to support a family.
D) warfare and economic depression reduced Europe's population by more than five million.
E) All these answers are correct.