What's one benefit of creating multiple ad groups?

What's one benefit of creating multiple ad groups?
  
A)  You can target specific ad groups into various Google networks
B)  You can break up keywords and ads into related themes
C)  You can set different budgets for each ad group
D)  You can pause specific keywords if they are not performing well

Answer : You can break up keywords and ads into related themes

Reason : 

Read at https://support.google.com/adwords/answer/2375452?hl=en

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