Answer: C.
Step-by-step explanation:
The colon is referred to as a punctuation mark that is made up of two dots that are placed above one another. A colon is normally used before a quotation, an explanation or a list.
Therefore, the sentences that used a colon correctly will be "We considered the following name for our cat: Smokey, Oscar, and Sock Thief".
Here, the colon is used before the list of the cats.