Passage Summary: Scientists saw a gas ring flickering at a specific speed, which means it's orbiting very close to a black hole, and that kind of close orbit is only possible if the black hole is spinning.

Reasoning: A specific flickering rate implies a 49km radius, and a radius that small near a black hole requires the black hole to be spinning.

Analysis: This stimulus provides a chain of facts that lead to a logical deduction. If the flickering rate confirms the radius, and the radius confirms the spin, then the flickering rate itself is evidence that the black hole is spinning. You should look for an answer that synthesizes these steps into a single statement, likely concluding that the black hole in question is indeed spinning.