June Recently Will Soon Undergo Magnetic Resonance Imaging (MRI) Scan

Multiple Choice

June recently will soon undergo magnetic resonance imaging (MRI) scan. Which of the following will the scan involve?

A) Narrow X-ray beams will pass through June's head, and the amount of radiation absorbed by each beam will be measured.
B) June will be injected with a radioactive isotope in order to show the different levels of activity in specific areas of her brain.
C) June will have to reconstruct with a pencil and paper several images that are presented to her.
D) A magnetic field will realign the hydrogen atoms in June's brain, allowing the computer to read the signals to construct images of her brain.