You have noticed that there is a persistent shortage of teachers in an inner-city school district in your state. Based on this observation, you suspect that:

A、thereisanexcesssupplyofteachers.;
B、thewageforteachersatthoseschoolsislowerthantheequilibriumwage.;
C、thereservationpriceamongteachersislowerthanforotherprofessions.;
D、thewageforteachersatthoseschoolsishigherthanatotherschoolsinthestate.