Astronomy current events question: Martian rock layers

Astronomy 210L, Spring Semester 2010
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!)

Jet Propulsion Laboratory news release, "Layers Piled in a Mars Crater Record a History of Changes," February 11, 2010
http://www.astronomy.com/asy/default.aspx?c=a&id=9417

Researchers at NASA's Jet Propulsion Laboratory have proposed a chronological history of water on Mars, based on evidence:
(A) from visual sketches of Mars seen through the first telescopes.
(B) deduced from the similar geological history of the Tibetan mountain steppes on Earth.
(C) analyzed from air bubbles released from melting polar ice samples.
(D) excavated and analyzed by Mars rovers.
(E) of hundreds of exposed rock layers in a crater observed from orbiting Mars.

Correct answer: (E)

Student responses
Sections 30678, 30679, 30680
(A) : 0 students
(B) : 1 student
(C) : 2 students
(D) : 1 student
(E) : 26 students