Wireless keyboards require batteries

In a situation where you want to perform one action when a Boolean expression evaluates as true and an alternate action when it evaluates as false, otherwise known as a dual-alternative decision, what sort of statement should you use?

A. if-else B. if C. switch D. fork

"Has this problem occurred more than once?", is an example of a(n) _________________ designed to get important information from a user and challenge assumptions a support agent has made.

Fill in the blank(s) with the appropriate word(s).