Task: Question Answering
Input (English): Passage: In 1976, Fred Wilson, an executive of the Petrox Oil Company, forms an expedition based on infrared imagery which reveals a previously undiscovered Indian Ocean island hidden by a permanent cloud bank. Wilson believes that the island holds vast untapped deposits of oil, a potential fortune which he is determined to secure for Petrox. Unknown to Wilson or the crew, Jack Prescott, a primate paleontologist who wants to see the island for himself, has stowed away on the expedition's vessel, the Petrox Explorer. Prescott reveals himself when he warns the crew that the cloud bank may be caused by some unknown, and potentially dangerous, phenomenon. Wilson orders Prescott locked up, believing him to be a corporate spy from a rival oil company. While being escorted to lock-up, Prescott spots a life raft which, upon inspection, is found to be carrying the beautiful and unconscious Dwan. After conducting a thorough background check on the 'spy', Wilson realizes that he is telling the truth and appoints Prescott as the expedition's official photographer, requesting that, due to his medical training, he be present when Dwan revives. When she does regain consciousness, Dwan states that she is an aspiring actress who was aboard a director's yacht, which suddenly and inexplicably exploded.
When the Petrox Explorer arrives at the island, the team discovers a primitive tribe of natives who live within the confines of a gigantic wall. The tribal chief shows an immediate interest in the blonde Dwan, offering to trade several of the native women for her, an offer firmly rejected by Jack. The team then learn that while the island does indeed contain large deposits of oil, it is of such low quality that it is unusable. Later that night, the natives secretly board the ship and kidnap Dwan, drugging her and offering her as a sacrifice to a giant ape known as Kong. Kong frees Dwan from the stronghold and retreats into the depths of the island. 
Question: What is the last name of the person who is found to be telling the truth after an interrogation?
Output (English): Prescott.