In multi$-$level feedback scheduling, $\_\_\_\_\_\_\_\_\_.$

a$.$

A process can move to a different priority ready queue.

b$.$

The priority of process after running is permanent.

c$.$

The proesses in the same queue is sequenced thus executed in FIFO.

d$.$

The changing behavior of a process such as from CPU$-$extensive to I$/$O bound cannot be captured.