Police Officers Were Stationed on a Hill 300 Yards from the Rear

Police officers were stationed on a hill 300 yards from the rear of the suspect's eighth floor apartment. With a telescope the officers could observe through the partially closed drapes at the rear that the suspect was engaged in an illegal activity. The officers' information _____.

A) was lawfully gathered because any aural or visual enhancement is allowed
B) was not lawfully gathered because they could not have seen the activity without some visual enhancement
C) was lawfully gathered because the suspect did not completely close the drapes
D) was not lawfully gathered because the suspect's reasonable expectation of privacy was violated