Question: I realized that someone had been _____ my food from the fridge since the beginning of the year.
Correct Answer: stealing
This question tests verb tenses (past perfect continuous). "Had been stealing" is correct because it shows an ongoing action (stealing) that started in the past ("since the beginning of the year") and was discovered later ("I realized").

Incorrect Answers:
- steal - Base form of the verb; doesn't fit the past perfect continuous structure ("had been + verb-ing").
- stolen - Past participle; used for passive voice or perfect tenses, not continuous actions.
- steals - Present simple tense; doesn't match the past context of the sentence.