The Main Source of Moderate-Energy Cosmic Rays, the High-Energy Atomic

Multiple Choice

The main source of moderate-energy cosmic rays, the high-energy atomic nuclei that strike Earth's atmosphere from interstellar space, is believed to be

A) rotating, magnetized neutron stars.
B) matter from accretion disks surrounding neutron stars and black holes.
C) acceleration of nuclei by neutrinos during supernova explosions.
D) supernova debris colliding with interstellar material.