"Here are two choices: pizza and hot dogs."
Would that be correct, or can the colon only introduce three or more objects?
"Here are two choices: pizza and hot dogs."
Would that be correct, or can the colon only introduce three or more objects?
Actually, colons can be used with any number of items, including just one:
Rule 1a. Use a colon to introduce an item or a series of items.
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Here's an example with 2:
It's correct to say, "Grammar Girl has two favorite hobbies: watching clouds and seeing how long she can stand on one foot."
Grammar Girl : Colons :: Quick and Dirty Tips ™
So, as long as you follow the other rules for when to use a colon (which you seem to be), any number of items can follow.