Please choose the correct answer to the question: A scientist conducts an experiment on the growth rate of a specific species of plant. Which of these is needed for the data to be relied upon by other scientists?

Answer1: The investigation must use many variables. Answer2: Equipment used in the investigation must be new. Answer3: Results of the investigation must be recorded accurately. Answer4: The investigation needs to be performed by well-known scientists.

Answer format: answer1/answer2/answer3/answer4