In which situation is it necessary for the state not only to make law but also enforce it?

Correct answer: When children are being made to work in mines

The direct answer is A: when children are being made to work in mines. Making a law is only the first step. Enforcement means checking workplaces, investigating violations, rescuing and protecting children, punishing offenders, and ensuring that the law works in real life. The reasoning is: mining is hazardous; children are especially vulnerable; child labour in such a place can harm health and education; therefore the State must actively enforce the prohibition, not merely write it in a legal book. Option A presents a real danger and requires inspection and action. Option B, peaceful speech, is a normal democratic activity and does not by itself show a law-enforcement problem. Option C, students studying, is a lawful and beneficial activity, so it does not call for enforcement against exploitation. Option D, people travelling, is ordinarily lawful and unrelated to hazardous child labour. Enforcement does not mean stopping every activity; it means applying protective laws when rights are threatened. Memory cue: a law protects only when authorities implement it.