Joshua, Who Is 19 Years Old, Can't Seem to Get

 Joshua, who is 19 years old, can't seem to get to sleep until about 2 a.m. and then struggles to get up on time in order to attend morning classes. It is most likely that Joshua

A) has always been an "owl" and will continue this pattern throughout his adulthood.
B) is currently an owl but may or may not change to another pattern during his 20s.
C) might not have been an owl previously but will now maintain this pattern for the rest of his life.
D) has been an owl up to young adulthood but will change to a new pattern later in his 20s.