Astronomy current events question: early galaxy dark matter

Astronomy 210L, spring semester 2017
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!)

Reinhard Genzel, Natascha M. Förster Schreiber, Hannelore Hämmerle, "Event Horizon Telescope Ready to Image Black Hole" (March 16, 2017)
mpg.de/11170451/early-galaxies-dark-matter

Very distant, early galaxies may have less dark matter than current galaxies, based on mapping the distribution of their stars':
(A) orbital velocities.
(B) brightness fluctuations.
(C) matter-antimatter ratios.
(D) neutrino emissions.
(E) fast radio bursts.

Correct answer: (A)

Student responses
Sections 30679, 30680
(A) : 10 students
(B) : 9 students
(C) : 8 students
(D) : 6 students
(E) : 0 students