Astronomy current events question: waterless carbon-rich exoplanets

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)

Whitney Clavin, "Carbon Worlds May be Waterless, Finds NASA Study," October 25, 2013
http://www.jpl.nasa.gov/news/news.php?release=2013-308

NASA Jet Propulsion Laboratory scientists proposed that carbon-rich exoplanets would lack water, based on comparing computer models of __________ in our solar system.
(A) carbon-14 decay.
(B) planet evolution.
(C) the greenhouse effect.
(D) diamond formation rates.
(E) carbon-based life.

Correct answer: (B)

Student responses
Sections 70178, 70186
(A) : 5 students
(B) : 11 students
(C) : 0 students
(D) : 10 students
(E) : 14 students