In which of the following situations would a personal automobile policy $($PAP$)$ NOT provide coverage under the liability section of the policy?

Question $20$ options:

a$)$

The named insured borrows a van while his covered auto is being repaired.

b$)$

The named insured uses his car to regularly transport executives to the airport for a fee.

c$)$

A resident relative, with permission, borrows a truck to haul some sod to his house.

d$)$

The named insured uses his trailer, which is hitched to his brother's truck, to move furniture.