Remember at the beginning of the movie where Kham had to say goodbye to Por Yai? Something that really caught my eyes was when Kham kneeled down and bowed, the elephant lifted up its trunk and growled over him. Why did it do that?

My guesses:

1. It was like a blessing, or like wishing good luck.
2. It was like Por Yai gave him "the gift" (his martial art skills).
3. He was saying goodbye.

Anyone know the significance behind this one little scene?