Please choose the correct answer to the question: A student uses a pH meter to measure the acidity of a water sample from a lake. For what purpose is the student most likely testing the water?

Answer1: to learn what organisms could survive in the lake Answer2: to determine the age of the lake Answer3: to understand how people use the lake Answer4: to find out the depth of the lake

Answer format: answer1/answer2/answer3/answer4