Given the task definition, example input & output, solve the new input case.
In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Example: Passage: Nearing London, Oliver encounters Jack Dawkins, a pickpocket more commonly known by the nickname the "Artful Dodger", and his sidekick, a boy of a humorous nature named Charley Bates, but Oliver's innocent and trusting nature fails to see any dishonesty in their actions. The Dodger provides Oliver with a free meal and tells him of a gentleman in London who will "give him lodgings for nothing, and never ask for change". Grateful for the unexpected assistance, Oliver follows the Dodger to the "old gentleman's" residence. In this way Oliver unwittingly falls in with an infamous Jewish criminal known as Fagin, the gentleman of whom the Artful Dodger spoke. Ensnared, Oliver lives with Fagin and his gang of juvenile pickpockets in their lair at Saffron Hill for some time, unaware of their criminal occupations. He believes they make wallets and handkerchiefs.
Output: Who believes Fagin's gang make wallets and handkerchiefs?.
This question is based on the following sentence in the passage "He believes they make wallets and handkerchiefs". It evaluates the understanding that the pronoun "he" refers to name "Oliver". You can ask questions like this one about most pronouns in a paragraph.

New input case for you: Passage: The Navajo were an Athabaskan people who migrated from the north into the Colorado River basin around 1025 A.D. They soon established themselves as the dominant Native American tribe in the Colorado River basin, and their territory stretched over parts of present-day Arizona, New Mexico, Utah and Colorado – in the original homelands of the Puebloans. In fact, the Navajo acquired agricultural skills from the Puebloans before the collapse of the Pueblo civilization in the 14th century. A profusion of other tribes have made a continued, lasting presence along the Colorado River. The Mohave have lived along the rich bottomlands of the lower Colorado below Black Canyon since 1200 A.D. They were fishermen – navigating the river on rafts made of reeds to catch Gila trout and Colorado pikeminnow – and farmers, relying on the annual floods of the river rather than irrigation to water their crops. Ute peoples have inhabited the northern Colorado River basin, mainly in present-day Colorado, Wyoming and Utah, for at least 2,000 years, but did not become well established in the Four Corners area until 1500 A.D. The Apache, Cocopah, Halchidhoma, Havasupai, Hualapai, Maricopa, Pima, and Quechan are among many other groups that live along or had territories bordering on the Colorado River and its tributaries.Beginning in the 17th century, contact with Europeans brought significant changes to the lifestyles of Native Americans in the Colorado River basin. Missionaries sought to convert indigenous peoples to Christianity – an effort sometimes successful, such as in Father Eusebio Francisco Kino's 1694 encounter with the "docile Pimas of the Gila Valley [who] readily accepted Kino and his Christian teachings". From 1694 to 1702 Kino would explore the Gila and Colorado Rivers to determine if California was an island or peninsula. The Spanish introduced sheep and goats to the Navajo, who came to rely heavily on them for meat, milk and wool. By the mid-16th century, the Utes, having acquired horses from the Spanish, introduced them to the Colorado River basin. The use of horses spread through the basin via trade between the various tribes and greatly facilitated hunting, communications and travel for indigenous peoples. More warlike groups such as the Utes and Navajos often used horses to their advantage in raids against tribes that were slower to adopt them, such as the Goshutes and Southern Paiutes.
Output:
What is the full name of the person who would explore the Gila and Colorado Rivers to determine if California was an island or peninsula?