单项选择题

Nathan was a fiercely ambitious and competitive man, as quick to take offence as to give it in his business dealings, and it is not difficult to imagine him responding ______to such______.

(A) mysteriously … an entreaty
(B) fractiously … a pleasantry
(C) self-effacingly … an invitation
(D) impetuously … a contretemps
(E) gravely … a leitmotif