Astronomy current events question: Sendai earthquake effects

Astronomy 210L, Spring Semester 2011
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!)

Alan Buis, "Japan Quake May Have Shortened Earth Days, Moved Axis," March 14, 2011
http://www.nasa.gov/topics/earth/features/japanquake/earth20110314.html

The Sendai earthquake in Japan may have shortened the length of Earth's day, and shifted its axis, according to:
(A) worldwide mismatches of atomic clocks.
(B) the sudden closeness of the moon's distance.
(C) the early start of daylight savings time.
(D) theoretical calculations.
(E) GPS data errors.

Correct answer: (D)

Student responses
Sections 30678, 30679, 30680
(A) : 3 students
(B) : 7 students
(C) : 0 students
(D) : 38 students
(E) : 3 students