【单选题】That large regions of the galaxy can be influenced by the formation of massive stars in a few localized regions requires that star formation somehow be coordinated over long periods of time. The proce...
A.
indicate the direction that research into a particular physical phenomenon should take
B.
illustrate the limitations of applying mathematics to complicated astrophysical phenomena
C.
clarify the differences between an old explanation of a physical phenomenon and a new model of it
D.
introduce a new explanation of a physical phenomenon
E.
explain the difference between two related physical phenomena