A closed organ pipe of length L and an open organ pipe contain gases of densities rho₁
and rho₂ respectively. The compressibility of gases are equal in both the pipes. Both
the pipes are vibrating in their first overtone with the same frequency. The length of the open organ pipe is:

A. √(3/4) L rho₁/rho₂
B. √(3/4) L rho₂/rho₁
C. √(4/3) L rho₁/rho₂
D. √(4/3) L rho₂/rho₁