A sales representative knowingly entered into a contract for an alarm system during a door$-$to$-$door sales campaign with an obviously mentally ill individual. Why could the contract be immediately rendered voidable at that individual customer$$s request?

a$.$

The contract is unenforceable because the alarm system was too complicated for the purchaser to understand.

b$.$

Establishing true consent is not possible due to the individual's incapacity to grasp the meaning and effect of the contract.

c$.$

The individual who purchased the alarm system is unsophisticated and failed to ask questions about the system.