What is the main idea of this text?
a. The Kepler space telescope was on a mission to find Earthlike exoplanets but its mission ended before it discovered anything.
b. Scientist Nick Gautier studies exoplanets to learn how planets form at NASA’s Jet Propulsion Laboratory in Pasadena, California.
c. Kepler-16b’s star system is located about 200 light-years from Earth and one light year is about 5.9 trillion miles.
d. The Keplar space telescope discovered Keplar-16b, a circumbinary planet, which was the first of its kind to be discovered.