Astronomy current events question: Jupiter's Red Spot color origins

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!)

Preston Dyches, "Jupiter's Red Spot Most Likely A Sunburn, Not a Blush," (November 11, 2014)
http://www.jpl.nasa.gov/news/news.php?feature=4372

Jet Propulsion Laboratory scientists propose that the color of Jupiter's Great Red Spot is due to chemicals reacting with sunlight, based on comparing observations with:
(A) increased activity due to solar flares.
(B) correlated auroral activity.
(C) decreasing wind speeds.
(D) samples brought back by the Cassini mission.
(E) experiments in Earth-based laboratories.

Correct answer: (E)

Student responses
Sections 70178, 70186
(A) : 8 students
(B) : 7 students
(C) : 4 students
(D) : 5 students
(E) : 13 students