Here come the beagles boilin hard for the bluff. They come so fast upon Bruh Deer's track, they never have a chance to stop. Two or three go on over the bluff, and they drop in the water right in front of Bruh Alligator's snout.

Which phrase in the excerpt provides a clue about what BOILING HARD means?

“come so fast”
“have a chance”
“over the bluff”
“in the water”