In the Context of Capacity to Contract,which of the Following

In the context of capacity to contract,which of the following statements is NOT correct?

A) Children of any age can deliver newspapers or pamphlets or advertising material provided they have written permission from their parents.
B) Children of any age can work in a family business provided it does not interfere with school attendance.
C) Children aged 13 or 14 can work in cafes or fast food outlets outside school hours with written permission from their parents.
D) All of the above.