Which of these uses the best transition?

a. in the story “to build a fire,” the author builds suspense by showing that the man's fingers freeze instantly when he removes his glove. by repeating words and using stark descriptions, the author conveys the feeling of extreme cold.
b. another technique that the author uses in the story is irony when he reveals that the dog is, in some ways, smarter than the man.
c. there are only two main characters in “to build a fire”—the man and his dog. however, through vivid description and foreshadowing, the author reveals a third important character—the freezing weather.
d. the story “to build a fire” is a monumental example of the conflict between man and nature. revealing to us how powerless we really are against nature's great forces.