The number machine shown uses a rule to change each number that is put into it to a different number. The same rule is used every time. The table given shows the results when three different numbers were put into the number machine. In Out 8 20 5 14 12 18 Which of the following could be the rule used by the number machine?

• A.  Add 12
• B.  Add 24
• C.  Multiply by 2, then add 4 to the result.
• D.  Multiply by 3, then subtract 4 from the result.