If you have to choose between the two..

Simple break up first then move on. No monkey branching allowed!

choose the person who cares for u...

I would never make that choice. I would hope everyone could act like adults and be respectful.

Why do i have to choose if i can have both?

You mean, like, if we are all 3 in a lifeboat?

The boyfriend can be replaced.

my ex boyfriend made me choose

Well, I think the op didn't phrase the post, well. Usually a Best friend becomes the boy friend. After that if a gal tells that new boyfriend, honey meet my new bf! Then that is monkey branching. A guy does that, he's called a player.... boom.

the exact question my ex boyfriend asked before that caused our breakup lol.. I have a guy bestfriend

Well that will happen. If you were a guy, and you like another girl as a friend. Don't you think your girlfriend would get jeleous? Sorry I like playing Devils advocate!

Well I have a Girl bestie and that will never change..
And my BF is my best friend period. if not then why would I want him

Owww ... I hope the Krupa has a life vest!! Poor bugger ...
I feel sad now

It depends. What is the reason for the BF asking that? You give us no context, other than making out to believe ex-lover is an a-hole.
If the other is a male best friend, I can understand a guy can be uncomfortable with that (The same the other way round btw).

Talking about it might help, provided of course the boyfriend has NO reason to be jealous/suspicious.

But even then to me it would still depend.
1 on the type of friendship. There's friends and there's friends. Even among best friends.

2 the stability / duration of the love relationship

3 the behaviour of my partner: is he like that all the time when I talk to another bloke? If he's constantly not trusting and jealous, I'd dump the boyfriend.

4 Do I spend more time on that friend than on my lover? Like getting calls/texts from friend all day every day, even at night, and I reply right away, regardless of what lover and I are doing?
If yes, then lover has every reason to not be happy about it. Serious reason to question why you're with him and not the male friend.

So no default answer. It just depends ... context.

Only if he were not the best friend also.

How does the saying go.. bros before hoes...lol

But.. really who am I kidding I would drop my best friends in a New York Minute.... to get with a hottie...lol

They say it's bad luck to drop mirrors .

..ohhh.. that's good!!. Lol..
... bet you been waiting a long time to use that one haven't you..lmao..
But all the same you got me good on that one

If my best friend told me he wasn't sure about the women I was seeing, I'd think about it. If the women I was with told me I couldn't see my best friend ever again it would be over but only because I've known the my friend for more then 30 years and he's like a brother to me.

Now if, like with your example, my best friend was a women, I would still feel the same way. Basically I would side with the person I've known long and tell the one I was seeing if they felt that strongly about it they can get lost.

Boy friend is a second stage of relationship and love . no one can hv both. The difference is that u can have sex with ur boyfriend but not with ur bestfriend.