Astronomy current events question: dark matter survey

Astronomy 210L, fall semester 2011
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!)

Astronomy.com editors, "Hubble Survey Carries Out a Dark Matter Census," October 13, 2011
http://astronomy.com/en/News-Observing/News/2011/10/Hubble%20survey%20carries%20out%20a%20dark%20matter%20census.aspx

The NASA/ESA Hubble Space is surveying the presence of dark matter by looking for:
(A) matter-antimatter annihilations.
(B) cosmic background radiation distortions.
(C) distant galaxies images distorted by gravity.
(D) concentrations of dark energy.
(E) pockets of empty, but energetic space.

Correct answer: (C)

Student responses
Sections 70178, 70186, 70200
(A) : 2 students
(B) : 3 students
(C) : 28 students
(D) : 5 students
(E) : 6 students