Which sentence uses commas correctly in a list of three or more items?
Options:
1. The students are required to bring, their textbooks, pencils and Zip disks to class.
2. The students are required to bring their textbooks, pencils, and Zip disks to class.
3. The students are required to bring their textbooks pencils and Zip disks to class.
4. The students are required to bring their textbooks, pencils and Zip disks to class.