Final answer:
The truth of the statement regarding the expiration of a birthday reward after 90 days depends on the specific terms and conditions of the birthday reward program involved. Verification with the particular program's policy is necessary to determine whether the statement is true or false.
Step-by-step explanation:
Without specific context, the statement "The birthday reward expires after 90 days" cannot be definitively classified as true or false, as expiration policies for birthday rewards can vary between different businesses or programs. One must refer to the specific terms and conditions of the particular birthday reward program in question to determine the validity period of the reward. If the terms of the program state that the reward expires after 90 days, then the statement would be true for that program. However, if the program specifies a different validity period, or if there is no expiration at all, the statement would be false. It is important for individuals to review the details of any birthday reward program they are a part of to understand the expiration policy.