Given the task definition, example input & output, solve the new input case.
This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.
Example: Passage: In 1763, Spain traded Florida to the Kingdom of Great Britain for control of Havana, Cuba, which had been captured by the British during the Seven Years' War. It was part of a large expansion of British territory following the country's victory in the Seven Years' War. Almost the entire Spanish population left, taking along most of the remaining indigenous population to Cuba. The British soon constructed the King's Road connecting St. Augustine to Georgia. The road crossed the St. Johns River at a narrow point, which the Seminole called Wacca Pilatka and the British named "Cow Ford", both names ostensibly reflecting the fact that cattle were brought across the river there.
Output: Who owned Cuba after the Eight Years War?
This question appears to be relevant to the passage as both involves words such as 'Cuba' and 'War' which also exist in the passage. The passage mentions that "after the war, almost the entire Spanish population left, taking along most of the remaining indigenous population to Cuba". This information is not sufficient to conclude that which country owned cuba.

New input case for you: Passage: In 1846, the United States went to war against Mexico and sent a naval and land expedition to conquer Alta California. At first they had an easy time of it capturing the major ports including San Diego, but the Californios in southern Alta California struck back. Following the successful revolt in Los Angeles, the American garrison at San Diego was driven out without firing a shot in early October 1846. Mexican partisans held San Diego for three weeks until October 24, 1846, when the Americans recaptured it. For the next several months the Americans were blockaded inside the pueblo. Skirmishes occurred daily and snipers shot into the town every night. The Californios drove cattle away from the pueblo hoping to starve the Americans and their Californio supporters out. On December 1 the Americans garrison learned that the dragoons of General Stephen W. Kearney were at Warner's Ranch. Commodore Robert F. Stockton sent a mounted force of fifty under Captain Archibald Gillespie to march north to meet him. Their joint command of 150 men, returning to San Diego, encountered about 93 Californios under Andres Pico. In the ensuing Battle of San Pasqual, fought in the San Pasqual Valley which is now part of the city of San Diego, the Americans suffered their worst losses in the campaign. Subsequently a column led by Lieutenant Gray arrived from San Diego, rescuing Kearny's battered and blockaded command.
Output:
Who commissioned Captain Archibald Gillespie to lead 500 men on horseback to the north?