Officer Allen Obtained a Search Warrant for Dan's Apartment After

Officer Allen obtained a search warrant for Dan's apartment after he arrested him for possession of stolen televisions. He obtained a key from the apartment building's manager. Officer Allen knew that Dan was in jail, so he let himself in with the key and did not knock. As soon as he was in the door he checked all the rooms to make sure no one would ambush him. While doing so, he found an illegal assault rifle in the back of a clothes closet in Dan's bedroom. He spent an hour searching the small apartment. He did not find any stolen televisions, but he did find counterfeit $20 bills in a wallet on top of Dan's dresser. Will the fact that Officer Allen entered the apartment without knocking result in everything that was seized being excluded from evidence at trial?

A) Yes, absent an emergency, officers must comply with "Knock-and-Announce."
B) Yes, the fact that Officer Allen conducted a protective sweep proves that he believed someone was in the apartment.
C) No, Officer does not have to comply with "Knock-and-Announce" because he knew Dan was in jail.
D) No, Officer Allen's failure to comply with "Knock-and-Announce" does not result in suppression of evidence because he was executing a search warrant.