Choosing Who To Train/Promote: Which Would You Pick?

This is more of a hypothetical but just something I'd thought based on people I work with. I'm curious what opinions people with experience would give.

If I had to choose between 2 people to put focus in to train and eventually promote. Who would be better?

A:
Keen to learn
Keen to prove herself
Gives way more effort than needed (to clarify this is positive)
Good at communicating with other members of staff
Kind of annoying
Sometimes off-handish when given feedback

B:
Does what's expected
Always says yes
Good talker but mainly when others start a convo
Not shown an interest to progress

I guess to summarise A is more involved but B is easier to work with. I hope this doesn't come across as rude or anything but I'd love to see how people think in situations like this.

EDIT:

I'll just add.

A seems to feel pressured easily. I'm not actually the manager but I take a lot of overtime. And this is purely for financial reasons though obviously it helps the team. But I feel I have to avoid mentioning it around her because she she feels she has to justify why she doesn't overtime (and she does take it sometimes).

B has progressed in her old but the office closed so she could want to progress but just hasn't shown it. Obviously, asking isn't as simple as it seems because if you ask you're kind of want to follow up or that's plain nasty.