The correct answers are Where did you hide the pepperoni pizza? and Why are you covered in tomato sauce?

Wh- questions follow this word order: Wh- word + Auxiliary Verb + Subject + Main Verb.

• "Where did you hide..." is correct. "Where you hid..." is missing the auxiliary verb "did."

• "Why are you covered..." is correct because the "to be" verb acts as the auxiliary and moves before the subject.

• "When did you ate..." is incorrect because after the auxiliary "did," the main verb must be in its base form ("eat," not "ate").