The header should encapsulate all aspects of the table.
Cans of food are brought by the teachers to be donated to the food drive. Hence the answer should be cans for food drive.
Cans recycled are out of context as the cans of food are for donation as seen in the table, not for recycling.
Favourite food and favourite teacher cannot be measured by the data provided which is which teacher bringing how many cans of food for donation. Hence, these 2 are not the answer as well.
