The correct answer is D. cm2/sec.
Kinematic viscosity is a measure of how easily a fluid flows. It is defined as the ratio of dynamic viscosity to density. The dynamic viscosity is a measure of how much resistance a fluid offers to deformation, while the density is a measure of how much mass a fluid contains per unit volume.
The units of kinematic viscosity are cm2/sec. This can be written in other ways, such as m2/s or ft2/s. The units of kinematic viscosity are derived from the units of dynamic viscosity and density. The units of dynamic viscosity are dyne-sec/cm2, and the units of density are g/cm3. Therefore, the units of kinematic viscosity are dyne-sec/cm2 / g/cm3 = cm2/sec.
Option A, gm/cm-sec2, is not a correct unit of kinematic viscosity. This unit is not dimensionally consistent with the definition of kinematic viscosity.
Option B, dyne-sec/cm2, is a correct unit of dynamic viscosity. However, it is not the unit of kinematic viscosity.
Option C, gm/cm2-sec, is not a correct unit of kinematic viscosity. This unit is not dimensionally consistent with the definition of kinematic viscosity.