If $v$ is the kinematic viscosity of air - water vapour mixture and $D_{A B}$ is the mass diffusivity of water vapour in air then the ratio $v / D_{A B}$ is known as

(A) Stanton number

(B) Prandtl number

(C) Schmidt number

(D) Sherwood number

If $v$ is the kinematic viscosity of air - water vapour mixture and $D_{A B}$ is the mass diffusivity of water vapour in air then the ratio $v / D_{A B}$ is known as

(A) Stanton number

(B) Prandtl number

(C) Schmidt number

(D) Sherwood number

127