Final answer:
A vendee loses the right to make use of the period of payment when they default on the initial payment.
Step-by-step explanation:
The correct answer is B) When he defaults on the initial payment. A vendee is someone who buys goods on credit, meaning they don't have to make the full payment immediately. However, if the vendee defaults on the initial payment, they lose the right to extend the payment period and must pay immediately.