The correct answer is ...make sure they are not touching each other...
Step-by-step explanation:
This excerpt explains the processes yeomen followed to grow and store apples in England. About storage, the passage specifies only "spotless apples" should be selected and yeomen had to "make sure they are not touching each other". This specific detail shows one bruised apple can spoil all the other apples if this is in contact with other apples. Due to this, yeomen avoided putting apples together or storing spoiled apples. According to this, from the options, the detail that supports the idea one bad apple can spoil the others is "make sure they are not touching each other."