Which of the following is the main topic of the passage

A．Words and phrases accepted by the majority for formal usage.
B．Words and phrases understood by the majority but not found in standard dictionaries.
C．Words and phrases that are understood by a restricted group of speakers.
D．Words and phrases understood by a large number of speakers but not accepted as formal us- ag

A．intended to be a sensible student with noble ideals
B．wanted to be an example of practicality and rationality
C．intended to be a combination of engineer and humanist
D．wanted to coordinate engineering with liberal-arts courses in college