If the chord of an arc of a circle is of length m, the height of the arc is n and the radius of the circle is r. Then, which one of the following is correct? यदि एक वृत्त की चाप की जीवा की लंबाई m मीटर की है, और चाप की ऊंचाई n है और वृत्त की त्रिज्या r है । तो, निम्नलिखित में से कौन सा सही है?

The relationship between chord length m, sagitta (height) n, and radius r in a circle is m² = 4n(2r - n). This formula comes from the fact that the radius to the chord's midpoint is perpendicular to the chord, forming a right triangle with half the chord (m/2) and the distance from center to chord (r-n). By the Pythagorean theorem: (m/2)² + (r-n)² = r², which simplifies to m² = 4n(2r - n). Option A is incorrect as it's missing the factor of 4, and option C is incorrect as it has 2n instead of 4n.