Final answer:
The type of discount being offered in the promotion is 20% off on all products. Hence, option a) is correct.
Step-by-step explanation:
The type of discount being offered in the following promotion is a) 20% off on all products. This means that customers will receive a 20% discount on the total price of any product they purchase.
For example, if a product costs $100, the discount would be $20, so the customer would pay $80.