What? What? What?

I didn't realize that selective hearing begins at an early age. My child's response to every question lately is "What?" I found myself answering the question up to four times before finally catching on. If she doesn't want to do what I'm asking her to do, she says, "What?" It's a delay tactic. Here's a sample conversation:

[Alyssa is watching a cartoon.]
Mommy: "Alyssa, it's time to get a bath."
Alyssa: "What?"
Mommy: "Come on, it's bath time."
Alyssa: "What?"
Mommy: "I said, let's go get a bath."
Alyssa: "What?"
Mommy [frustrated]: "Movie time is over, it's bath time. Let's go!!!"
Alyssa: "What?"