Which correctly defends the author's use of a colon in the following sentence? I've decided not to try out for varsity football next year: the new coach expects all players to attend a four-week summer camp! A) The colon is used to introduce an elaboration of the main clause. B) The colon is used in place of a hyphen for the compound modifiers. C) The colon is used to indicate an elaboration of the dependent clause. D) The colon is used at the end of a heading which introduces a new section of a document.