The word "hypotheses" (Line 3, Para. 2) can probably be replaced by______.

A．in science, it is not difficult to tell fact from fiction______.
B．the meaning of science is so ambiguous that a few can catch on to its meaning and objectives
C．the fact that scientists ignored the practical side of their discoveries in theoretical research which should be introspected
D．practical-minded people can accurately explain the meaning and objectives of science as a whole

A．is not always as practical as applied science
B．necessarily comes after applied science
C．may cause a multitude of immediate result if properly made use of
D．necessarily emerges from applied science