the total area of the field average rainfall in the area all the organisms living in the field energy and nutrient requirements of dandelions
I gave my students this multiple choice question: A student wants to estimate the number of dandelion plants growing in a field. He counts the number of plants in a 5 square meter section of the field. What other information should he obtain to make his estimate?

Only one answer is correct among these 4 choices:
- the total area of the field
- average rainfall in the area
- all the organisms living in the field
- energy and nutrient requirements of dandelions

Could you tell me which one is correct?

the total area of the field