Definition: In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: When was Ōe Tokihiro's father born? Passage:The first castle on this site dates to the middle of the Kamakura period. Ōe Tokihiro, the younger son of Ōe no Hiromoto, a senior retainer of the Kamakura shogunate was granted lands in Dewa Province, and in 1238 changed his name to Nagai Tokihiro. The Nagai continued to rule for about 150 years. The Nagai were supplanted in the Sengoku period by the Date clan, and the famed warlord Date Masamune was born at Yonezawa Castle. After Date Masamune defeated the Ashina clan in 1589, he moved his main castle to Kurokawa Castle in Aizu and put Date Munekiyo in charge of Yonezawa. However, Toyotomi Hideyoshi did not agree, and forced Masamune move back to Yonezawa. In 1591, Masamune relocated to Iwadeyama Castle by orders of Hideyoshi, surrendering Yonezawa Castle to Gamō Ujisato. When Ujisato’s son, Gamō Hideyuki was moved to Utsunomiya in 1597, the castle was turned over to Uesugi Kagekatsu, as part of their vast 1,200,000 koku holdings based in Aizu. The castellan at this time was Naoe Kanetsugu.


b