Please choose the correct answer to the question: What would be the best way to determine the role of squirrels in a forest ecosystem?

Answer1: measure the length and mass of several squirrels Answer2: determine the genes that control squirrel traits Answer3: make field observations of squirrels in their natural habitat Answer4: read articles about the energy and nutrient requirements of squirrels

Answer format: answer1/answer2/answer3/answer4