This answer is honestly completely opinionated. For me, I think music is the closest thing we have to mind control. It can make you happy when you aren’t, or vice versa. It can make you do inexplicable dance moves that are just lovely. But this is a question completely up to you.
The answer is B
The first and third note are quarter notes for which only take one beat, the middle note is an eight note which also only takes one beat!
They used bright pastel colors is probably my best guess, but if that were the case I’m sure you would’ve picked that right?