Observations of neutrinos from the Sun have
Select one:
A. Shown that there is a problem with our theoretical models of the Sun because too few neutrinos are observed.
B. Proved too difficult to make because neutrinos react so weakly with ordinary matter and pass straight through the Earth.
C. Led to modifications of our understanding of particle physics.
D. Helped to detect the dark matter that makes up a substantial fraction of the universe.