Certainly the last two, I might even have the odd quality one in my selection.
View attachment 289454
Your sables look like they need a bit of TLC, You might like to try old-fashioned brush restorer, you know, the blue stuff (polyclens??) you soak the brushes then wash them through with cold water, works very well. When I say soak them, I mean use a clothes peg to keep the bristles suspended in the liquid (Obvs NEVER leave any brush standing in any liquid, guaranteed to ruin them).
Acrylic paint is tricky to remove from the place it hurts most, i.e. at the ferrule end (it's this build up that causes the bristles to start spreading outwars).
Mr Muscle is very good at softening the old paint, so you might want to try this first. Cellulose Thinners can be used as a last resort, but to be honest, Mr Muscle Blue window cleaner is excellent!
But... prevention is better than cure in this instance, and I'd heartly recommend a more robust cleaning regime, especially with any good sables you own. I have a bottle of Mr Muscle handy at all times, I first wash the majority of paint out in water, run the brush over a kitchen towel to dry it, then give it a good workout in the Mr Muscle, ending up by holding the brush, bristles outward, in your hand, and gently digging your thumbnail into the bristles right at the ferrule, you will see little particles being dislodged as you push the nail forward. As soon as you see the particles, shake the brush in some clean water and repeat until clean!
This takes a while, but if you own 40 odd brushes, it'll save you a fortune, and many brushes improve with normal use, so it's a win win
.