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: How long was the reign of the person who claimed all the land of England at the Norman conquest of England? Passage:At the Norman conquest of England, all the land of England was claimed as the personal possession of William the Conqueror under allodial title. The monarch thus became the sole "owner" of all the land in the kingdom, a position which persists to the present day. He then granted it out to his favoured followers, who thereby became tenants-in-chief, under various contracts of feudal land tenure. Such tenures, even the highest one of "feudal barony", never conferred ownership of land but merely ownership of rights over it, that is to say ownership of an estate in land. Such persons are therefore correctly termed "land-holders" or "tenants" (from Latin teneo to hold), not owners. If held freely, that is to say by freehold, such holdings were heritable by the holder's legal heir. On the payment of a premium termed feudal relief to the treasury, such heir was entitled to demand re-enfeoffment by the king with the fee concerned.


b