Please choose the correct answer to the question: Scurvy is a disease that sailors often got on long voyages. It was discovered that scurvy could be prevented by eating oranges and lemons. This suggests that scurvy is a disease caused by

Answer1: exposure to sea air Answer2: a nutritional deficiency Answer3: a microorganism Answer4: lack of exercise

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