The Number of Confirmed Extrasolar Planets

Multiple Choice

The number of confirmed extrasolar planets

A) was about 800 at the time of publication but is rising rapidly due to new observations by the Kepler spacecraft.
B) is about 600, and is not expected to rise very much.
C) is about 800, and is rising slowly, as observations are quite difficult.
D) has been decreasing as some observations thought to be planets have been disproven.
E) is zero; there are observations thought to be of extrasolar planets but none has yet been confirmed.