Non-Muslims were second-class citizens who endured prejudice, appears to contradict most directly Barkey's assertion in the first sentence of the first paragraph. The correct answer is option C.
The first sentence of the first paragraph states that the Ottoman Empire was known for its religious tolerance. To determine which claim by Barkey contradicts this assertion, we need to evaluate each option.
Option A claims that Ottoman administration played an important role in fostering tolerance in the empire. This statement aligns with Barkey's assertion and does not contradict it.
Option B states that Ottoman tolerance helped maintain peace and order. This claim supports the idea of tolerance within the empire and is not contradictory.
Option C asserts that non-Muslims were second-class citizens who endured prejudice. This claim contradicts the notion of religious tolerance mentioned in the first sentence of the first paragraph. If non-Muslims were treated as second-class citizens and faced prejudice, it suggests a lack of religious tolerance.
Option D claims that the Ottoman Empire's policies ensured that interethnic strife did not occur. This claim does not directly contradict the assertion in the first sentence, as it does not address religious tolerance explicitly.
Therefore, option C, which states that non-Muslims were second-class citizens who endured prejudice, appears to contradict most directly Barkey's assertion in the first sentence of the first paragraph.