Astronomy current events question: Pluto's floating water-ice hills

Astronomy 210L, spring semester 2016
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!)

Tricia Talbert, "Pluto’s Mysterious, Floating Hills" (February 4, 2016)
nasa.gov/feature/pluto-s-mysterious-floating-hills

Small, isolated water ice hills may be __________ on top of nitrogen ice glaciers on Pluto's surface.
(A) greenhouse gas sources.
(B) active cryovolcanoes.
(C) carried along.
(D) filled-in impact craters.
(E) harboring photosynthetic life.

Correct answer: (C)

Student responses
Sections 30678, 30679, 30680
(A) : 1 student
(B) : 5 students
(C) : 23 students
(D) : 10 students
(E) : 2 students