I don't think the other two really apply to him.

It was really amazing that he changed for his love♥

His character is strong and I dont just mean physically but personality wise. When he says no he meant no, he wasn't fickle unlike other characters in his movie. When he was a brat he was a brat, when he realized he loved Belle he acted accordingly. I can't say he changed good because his character didn't really change but more his choices. He was still quick to throw a fight but he learned not to be so quick and that didn't make him bad just difficult

Out of the three choices given, "changing to be good" fits the best. I'd actually give him the prize for self sacrifice for love.

Beast was neither strong nor adventurous. He's actually the second weakest of the Disney Princes (just barely stronger than Naveen). He's suicidally depressed, and never more so than after he lets Belle go. He has been hopelessly depressed for ten years, and his brief glimmer of joy with Belle just leaves him even more hopeless than ever. After he sacrifices his one and only hope, he just gives up.

The thing which elevates Beast's sacrifice above all the others is that Belle never even finds out! Beast sacrifices his only hope due to his love for Belle, knowing she'll never know what he did for her. And he's right! Just, not in the way he thought.

Beast thought Belle would never find out because he'd never see her again. The truth would be more complicated. Belle's biggest fault is that she assumes everyone else can tell what she's thinking without her coming out and saying it. She doesn't think she has to explicitly say she finds Gaston disgusting. She doesn't think she has to explicitly say she's coming back to the castle. She doesn't think she has to say how she feels about Beast.

When Belle does return, she doesn't understand why Beast is surprised at this. She just thinks, "Of course I came back!"

Presumably, Belle finds out the full truth about Beast's curse after the curse is lifted. Beast and/or the servants would have told her soon enough. But she still wouldn't know or understand the crucial thing that made Beast's sacrifice a sacrifice. Belle wouldn't know or understand that Beast thought he was saying goodbye to her forever!

Belle just thought, "Oh, I'm going to save my papa and then I'll be back as soon as I can--because of course I don't want to spend any more time away from my dear Beast than I have to."