I claim the ornamental design for a ventilation hood, as shown and described.
FIG. 1 is a rear perspective view of a ventilation hood, showing my new design;
FIG. 2 is a bottom perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a left side elevational view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
The dash-dot-dash broken lines illustrate the bounds of the claim. All other broken lines, illustrate portions of the ventilation hood. None of the broken lines form part of the claimed design.