Henry noted all of the following changes in Wilson except which? A) better at cooking meat on a stick B) not so pompous about his physical prowess C) less irritated by trivialities D) more inner strength to help others

I'd go with "A"

Your answer would be A) better at cooking meat on a stick. See the following passage:

"The youth took note of a remarkable change in his comrade since those days of camp life upon the river bank. He seemed no more to be continually regarding the proportions of his personal prowess. He was not furious at small words that pricked his conceits. He was no more a loud young soldier. There was about him now a fine reliance. He showed a quiet belief in his purposes and his abilities. And this inward confidence evidently enabled him to be indifferent to little words of other men aimed at him."