The correct option is D Both A and C.
There are major disadvantages of having a large family. One of the biggest disadvantage is negligence of each and every child by their parents. If there is small family, each child receives more attention from his parents.
If there is large number of children, there is simply not enough money to get everything for each child. Also, there is reluctance in child's proper nutrition care and medical care.
Thus, the correct answer is option (A).