The word "perilous" (Sentence 2, Para. 5) means" ______ ".

A．Demanding and challenging job.
B．Decent and respectable job.
C．Tough and difficult job.
D．Comfortable and well-paid job.

A．People now strive for better education in exactly the same way they did in the past.
B．At present a person may be driven to better his education not only by his thirst for knowledge but also by the pressure from their peers and employers.
C．Students of the past were more tolerant of poor performance of their classmates at school.
D．Employees now who do not undertake extra study may find their salary decreased by employers.