|Question 18Verbal

Source Texts

Text
Although 2060 Chiron and 2008 FC76 are both classified as centaur objects—outer solar system bodies in unstable orbits—they exhibit striking differences in _____ object 2060 Chiron is considered an active centaur, showing sporadic comet-like activity (such as clouds of dust and gas on its surface), 2008 FC76, showing no such activity, is considered dormant.
Which choice completes the text so that it conforms to the conventions of Standard English?
behavior; the
A
behavior. The
B
behavior, while the
C
behavior: while the
D