Hi,
This is an exam so I'm not going to feed you the answer, but I'll give you a few tips.
B is almost a dead-giveaway that it's incorrect. Why? It's vague, uses the word "just", and seems immature. You can pretty much cross that one out.
A and D could both be right, as long as they're backed up by evidence. Usually, this means you read a short essay before answering, and the answer lies in your reading.
C is a general answer (which could either be safe or unsafe), but is also unable to be proven wrong. It's true that children of any age require different care than children of a different age.
Good luck, and have fun
