Astronomy current events question: early-universe monster star clusters

Astronomy 210L, spring semester 2015
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!)

Shantanu Basu and Robert Massey, "As Bright as a Hundred Million Suns: the Clusters of Monster Stars that Lit Up the Early Universe" (April 22, 2015)
https://www.ras.org.uk/news-and-press/2617-as-bright-as-a-hundred-million-suns-the-clusters-of-monster-stars-that-lit-up-the-early-universe

University of Western Ontario in Canada researchers claim that the first stars born in the universe were extremely bright and clustered in small groups, based on:
(A) extremely redshifted galaxies.
(B) dark matter filaments.
(C) heavy elements found today.
(D) computer simulations.
(E) look-back time.

Correct answer: (D)

Student responses
Sections 30678, 30679, 30680
(A) : 11 students
(B) : 5 students
(C) : 8 students
(D) : 17 students
(E) : 8 students