Astronomy current events question: HL Tau protoplanets

Astronomy 210L, fall semester 2014
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!)

Charles E. Blue, "Birth of Planets Revealed in Astonishing Detail in ALMA's 'Best Image Ever,'" (November 6, 2014)
https://public.nrao.edu/news/pressreleases/planet-formation-alma

The Atacama Large Millimeter/submillimeter Array (ALMA) imaged planets forming around the star HL Tau, using wavelengths longer than visible light that are:
(A) absorbed by young protostars.
(B) emitted by residual photons.
(C) unaffected by Earth's atmosphere.
(D) resistant to redshifting.
(E) not blocked by gas and dust.

Correct answer: (E)

Student responses
Sections 70178, 70186
(A) : 7 students
(B) : 7 students
(C) : 4 students
(D) : 3 students
(E) : 16 students