It can be inferred that proper amounts of iodine, fluoride and calcium can ______.

A．It has given her due attention as well as help.
B．Adult students should be able to control their own behavior.
C．It is more than the school's responsibility to supervise the students.
D．Colleges can be a breeding ground for psychiatric problems.

A．she couldn't get enough eoncern from Syracuse University
B．she wasn't physically healthy enough to continue schooling
C．she still kept thinking about killing herself whenever at school
D．she has been troubled by the memory of the incident very often