As I study for my IRA written, this (VFR) question resurfaced and continues to irk me. The annotations cite the Venturi effect as the sole reason, but I don't follow.
From Wikipedia: "The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe"
Do we consider the parcel of air in the cabin to be the fluid moving through the constricted section of some imaginary/abstract pipe? If so, why? Can anyone shed more intuition on this?