The first sentence about Siamese cats is correct because the hypens are correctly placed where you pause when reading. The other answers have misplaced the hypens and they aren't in the appropriate place for pausing.
Answer: 4.the second clause contains a quotation.
Explanation:
Colons (:) are used in sentences to show that something is following, like a quotation, example, or list. A colon can be used to separate two independent clauses when a) the second clause is directly related to the first clause (not just vaguely related) and b) when the emphasis is on the second clause.
