JEE Main 2019 Physics question

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)decreases by a factor of
• (B)increases by a factor of 27Correct
• (C)decreases by a factor of 9
• (D)increases by a factor of 3