no-brainer
noun /ˌnəʊ ˈbreɪnə(r)/
/ˌnəʊ ˈbreɪnər/
(informal)- a decision or a problem that you do not need to think about much because it is obvious what you should do
- The question of who to support in this election should be a no-brainer.
- I said yes straight away. It was a no-brainer for me.