Answer: D. Child laborers help provide for their families, while child slaves work without pay
Explanation:
Child labour refers to the work done by children whereby they're deprived of their childhood, dignity and potential. These are harmful to the mental and the physical development of such children and dangerous for them. In this case, the child is paid and children oft go into these in order to support their poor families. Examples include children who work as houseboys, cleaners etc.
Child slavery refers to the enforced exploitation of a child and this is usually at the gain of someone else. In this case, the child isn't paid and often cannot leave.
In both cases, the children aren't usually protected and suffer depression and malnutrition.