In $2025,$ Alice provided over half the support of her son, Mike, age $20,$ who is a full$-$time college student. Assuming all of the other qualifying child tests are met, what is the maximum age that Mike can be a full$-$time student and still qualify to be listed as Alice's dependent?

A$)$

$21$

B$)$

$23$

C$)$

$18$

D$)$

$19$