Astronomy current events question: dark matter in galaxy Dragonfly 44

Astronomy 210L, fall 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!)

Jim Shelton, "Scientists Discover a 'Dark' Milky Way" (August 25, 2016)
news.yale.edu/2016/08/25/scientists-discover-dark-milky-way

The galaxy Dragonfly 44 is almost entirely composed of dark matter, as determined by measurements of __________ by telescopes at the W.M. Keck Observatory and the Gemini North Observatory.
(A) gravity waves.
(B) the central supermassive blackhole.
(C) star velocities.
(D) antimatter pockets.
(E) type Ia supernovae.

Correct answer: (C)

Student responses
Sections 70178, 70186
(A) : 7 students
(B) : 4 students
(C) : 17 students
(D) : 4 students
(E) : 0 students