Answer:
d. rods
Explanation:
In the retina there are two types of cells that are light sensitive: the rods and cones. Rods come in for so-called monochromatic vision in low or rare light, while the icons are activated in strong normal light to see the details. In this case, we can say that when Stewart wakes up at night and has to go from bedroom to bathroom in the dark, he is most directly assisted in this process by the rod cells.
