Which one of the following sentences contains an unnecessary colon?
A. Here's the question on all of our minds: Will our team be able to defeat their arch rivals tonight?
B. I wrote my shopping list and put: milk, soup, chicken, and ice cream on it.
C. She wants one thing: a new job.
D. Carlos has three goals in life: to graduate from college, own his own home, and work in the computer industry.
So, Colons are usually used in sentences to seperate ideas, or to make a point. So, above, the sentence that would be more or less incorrect would be B, because there is no need for a colon.