|Question 17Verbal

Source Texts

Text
Recent analysis of 2010 BL4-an outer solar system object orbiting the Sun between Jupiter and Neptune has determined its color to be gray, suggesting an icy composition. Such interpretations are ultimately        the object's gray coloration may be an incidental effect of radiation, solar wind, or collisions with other objects rather than evidence of its physical makeup.
Which choice completes the text so that it conforms to the conventions of Standard English?
speculative, though;
A
speculative, though,
B
speculative; though
C
speculative, though
D