The sentence "if he is blown" in Par

A．is the most frequent reason for dropping out
B．is more difficult for the science candidate than for the humanities candidate
C．is an essential part of many Ph.
D．programsD. does not vary in difficulty among universities

A．dropouts are substantially below Ph.D. s in financial attainment
B．the incentive factor is a minor one in regard to pursuing Ph.D. studies
C．the Ph.D．candidate is likely to change his field of specialization if he drops out
D．about one-third of those who start Ph.D．work do not complete the work to earn the degree