【单选题】

Hopefully scientific progress in AIDS research will continue at______pace, but nevertheless a current attitude of______prevailing among some biomedical researchers is rather inappropriate.
A．(A) a rapid … hubris

B．(B) an alarming … concern
C．(C) an optimistic … fastidiousness
D．(D) a leaden … nonchalance
E．(E) a vitiated … arrogance