Astronomy current events question: interstellar origins of Stardust dust grains?

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!)

Robert Sanders, "Seven Tiny Grains Captured by Stardust Likely Visitors from Interstellar Space," August 14, 2014
http://newscenter.berkeley.edu/2014/08/14/seven-tiny-grains-captured-by-stardust-likely-visitors-from-interstellar-space/

University of California at Berkeley scientists will be testing dust samples obtained by NASA's Stardust spacecraft to determine if these samples:
(A) are harder than diamonds.
(B) can be used to make superconductors.
(C) are still radioactive.
(D) contain building blocks for life.
(E) came from outside the solar system.

Correct answer: (E)

Student responses
Sections 70178, 70186
(A) : 0 students
(B) : 1 student
(C) : 5 students
(D) : 12 students
(E) : 26 students