When the jockey had a cold at the Kentucky Derby, everyone said that he was a little hoarse.

a. Pun

b. Oxymoron

c. Irony

d. Metaphor

The answer is a pun. Because a jockey rides a horse and he's a little hoarse: it's not spelled the same but it sounds the same (funds like horse) and since the jockey rides the horse, this is a pun.

An oxymoron is a word (in a sentence) that condradits itself (and the sentence). So it cannot be this. Ex: it was bittersweet.

Irony is when the language of an expression suggests one meaning but with irony, normally signifies the opposite meaning. So, it cannot be this.

Metaphor's are when an object symbolizes something important in a passage/book. So, it cannot be this.