Astronomy current events question: exoplanet Kepler-1625b's moon

Astronomy 210L, fall semester 2019
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!)

Mike Wall, "Neptune-Size Exomoon Candidate May Be the Captured Core of a Giant Planet" (September 26, 2019)
space.com/neptune-size-exomoon-giant-planet-core.html

Researchers propose that the moon orbiting exoplanet Kepler-1625b may actually be a:
(A) frozen comet.
(B) brown dwarf.
(C) a dwarf planet.
(D) a primordial black hole.
(E) core of another exoplanet.

Correct answer: (D)

Student responses
Sections 70178, 70186
(A) : 1 student
(B) : 2 students
(C) : 3 students
(D) : 0 students
(E) : 29 students