A copper wire is wound on a wooden frame, whose shape is that of an equilateral triangle. If the linear dimension of each side of the frame is increased by a factor of 3, keeping the number of turns of the coil per unit length of the frame the same, then the self-inductance of the coil

• A. Increases by a factor of 3
• B. Decreases by a factor of 9\(\sqrt 3\)
• C. Increases by a factor of 27
• D. Decreases by a factor of 9