Task: Question Answering
Input (English): Passage: In 1932, a luxury yacht is sailing through a channel off the western coast of South America. The captain is worried about the channel lights not matching the charts, but is quickly dissuaded from changing course by the wealthy passengers for the sake of time, including famous big game hunter and author Bob Rainsford. It is a calm evening, with the cheerful passengers relaxing over drinks and a game of cards. Bob and his companions are debating about whether hunting is at all sporting for the animal being hunted after a friend asks if he would exchange places with a tiger he had recently hunted in Africa. Bob replies that there are two kinds of people in the world: those who hunt and those who are hunted.
The ship suddenly runs aground, causing the ship to take on water and heave violently. Water floods the boiler room, causing the ship to explode and sink into the channel. Rainsford and two others manage to get away and cling to wreckage, but the other survivors are eaten by a shark. He swims to a small, lush island. Wandering through the jungle, he sees the channel lights off the shoreline change, and suspects the ship was deliberately led off course to its doom.
He stumbles across a luxury chateau where he becomes the guest of the expatriate Russian Count Zaroff, a fellow hunting enthusiast. Zaroff remarks that Rainsford's misfortune is not uncommon; in fact, four people from the previous sinking are still staying with him: Eve Trowbridge, her brother Martin, and two sailors.
That night, Zaroff introduces Rainsford to the Trowbridges and reveals his obsession with hunting. During one of his hunts, a Cape buffalo inflicted a head wound on him. He eventually became bored with the sport, to his great consternation, until he discovered "the most dangerous game" on his island. Rainsford asks if he means tigers, but Zaroff denies it. 
Question: What is the last name of the person who became bored with hunting?
Output (English): Zaroff.