QUESTIONS 36–42 ARE BASED ON THE FOLLOWING PASSAGE.D.A COMPANY CONTROL...

39. The word that can best be interchanged withwith the magnetic field like tiny bar magnets, and thehyperpolarizationin the passage isa.visualization.nucleus at the center of each atom spins constantlyabout its north-south axis. Inside the MRI scanner,b.alignment.c. emission.a radio pulse temporarily knocks the spinning nucleiout of position, and as their axes gradually realignd.tomography.within the magnetic field, they emit faint radio sig-