Help the detective confront the messy suspect by choosing the correct verb tense.

Your clothes are covered in flour and you look exhausted. What exactly __________ in the kitchen for the last three hours?

The correct answer is have you been baking.

The Present Perfect Continuous is perfect for this situation! It describes an action that has been happening over a period of time up until recently, and has left visible evidence or results in the present (the flour on the clothes and the exhaustion). The phrase "for the last three hours" confirms the need for a perfect tense.