A is correct because before adding a colon in any sentence it is really important that the preceding is a complete sentence. For example, "The little boy proudly wrote the letters of his first name" is a complete sentence while "<span>The people he wants to show his paper to are" is not a complete sentence.</span>
Hi
It used for pick up clues about written material.
I hope that's help!
It’s either A or C. i’m not really sure
