It ate more food. It was more active. It drank more water. It received more sunlight.
I gave my students this multiple choice question: Six puppies were born at the same time. After 6 months, one of the puppies was much heavier than the others. Which of the following is the most likely explanation for difference in size of that puppy?

Only one answer is correct among these 4 choices:
- It ate more food.
- It was more active.
- It drank more water.
- It received more sunlight.

Could you tell me which one is correct?

It ate more food.