Astronomy current events question: replicating quartz crystal formation in Earth's core

Astronomy 210L, spring semester 2017
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!)

Emiko Kawaguchi, "'Quartz' Crystals at the Earth's Core Power Its Magnetic Field" (February 23, 2017)
elsi.jp/en/news/highlights/2017/02/201702_pressrelease_hirose.html

Quartz crystals may be forming deep within Earth to help provide its magnetic field, according to researchers using __________ to replicate conditions within Earth's core.
(A) a nuclear fusion furnace.
(B) diamonds squeezed together.
(C) computer simulations.
(D) fresh molten lava.
(E) particle accelerators.

Correct answer: (B)

Student responses
Sections 30679, 30680
(A) : 4 students
(B) : 17 students
(C) : 4 students
(D) : 3 students
(E) : 1 student