For the function $=$VLOOKUP$($C$6,$ D$12$:F$18,3)$ to correctly work$/$function$,$ which of the following must happen?

a$.$ The entries in cells F$12$ through F$18$ must be in ascending order.

b$.$ The entries in cells F$12$ through F$18$ must be in descending order.

c$.$ The entries in cells D$12$ through D$18$ must be in ascending order.

d$.$ The entries in cells D$12$ through D$18$ must be in descending order.