Please choose the correct answer to the question: Several interchangeable parts are used in the manufacture of automobiles. Some examples of these parts are batteries, windshield wiper blades, spark plugs, and tires. Which of the following is an advantage of interchangeable parts over non-interchangeable parts on automobiles?

Answer1: Interchangeable parts are generally more expensive than custom-made parts for automobiles. Answer2: Interchangeable parts break more often now than in years past on most automobiles. Answer3: Interchangeable parts are plentiful for custom-made automobiles. Answer4: Interchangeable parts can fit many kinds of automobiles.

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