Astronomy current events question: x-rays from Milky Way center

Astronomy 210L, Fall Semester 2009
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!)

Astronomy.com editors, "New Vista of Milky Way Center Unveiled," September 23, 2009
http://www.astronomy.com/asy/default.aspx?c=a&id=8651

What properties of x-rays make it possible for the NASA Chandra X-ray Observatory to study the center of the Milky Way? Circle your answer below.
(A) Not blocked by interstellar gas and dust.
(B) Can escape from the central supermassive black hole.
(C) Energetic enough to disrupt ground-based instruments.
(D) Not detectable anywhere on Earth.
(E) Readily passes through the Earth's atmosphere.

Correct answer: (A)

Student responses
Sections 70178, 70186, 70200
(A) : 14 students
(B) : 7 students
(C) : 2 students
(D) : 1 student
(E) : 6 students