What does the proverb a leopard doesn't change it's spots mean

What is the best prediction of the meaning of thrilling based on the context clues?

Read the passage first of all if someone says your dream is impossible, they’re wrong. you can’t prove that something is impossible-all you know is that[it] hasn’t been done yet. people said no one could scale mount everest but in 1953, sir edmund hilary and tenzing norway gazed down upon the world from it’s summit. people said that man could not fly, but in 1903, orville and wilbur wright made the first sustained powered flight in a heavier-than-air machine. people said, “okay, we admit that someone could climb mount everest, and we admit that man has learned to fly, but no one will ever, ever walk on the face of the moon.” if we can send three men a quarter of a million miles away and bring them home safely, is there any great task we cannot accomplish? which identifies the textual evidence that best supports the claim: the authors purpose is to persuade? a: the author shares historical information about the wright brothers. b: the author states that men have walked the moon. c: the author states that others who think your dreams are impossible are wrong. d: the author wants to know what tasks we cannot accomplish.

Read the excerpt from "the most dangerous game." again rainsford lifted the heavy knocker, and let it fall. the door opened then, opened as suddenly as if it were on a spring, and rainsford stood blinking in the river of glaring gold light that poured out. the first thing rainsford's eyes discerned was the largest man rainsford had ever seen—a gigantic creature, solidly made and black bearded to the waist. in his hand the man held a long-barreled revolver, and he was pointing it straight at rainsford's heart. the details of this excerpt show that rainsford sees ivan as a(n) individual.