Please choose the correct answer to the question: Lori owns a house next to the lake. She uses lots of fertilizer to keep her lawn green. Which impact could fertilizing her lawn have on the lake?

Answer1: an increase in the algae population Answer2: an increase in the fish population Answer3: an increase in the mosquito population Answer4: an increase in the lake's depth

Answer format: answer1/answer2/answer3/answer4
Answer: answer1