An online retailer promises to provide cashback of $$100$ while exchanging an old phone for a new one. What the retailer does not specify is that the cashback amount will be credited to the purchaser's account in the form of shipping credit and that the amount may vary based on the condition of the phone. In the context of categories of ethical dilemmas, which of the following categories is exemplified in this scenario?

a$.$ Divulging information

b$.$ Engaging in conflict of interest

c$.$ Saying things that are pot true

d$.$ Taking things without permission