How does auxin produce phototropism? How does auxin produce phototropism?
A. Auxin accumulates in cells on the side of the plant facing the source of light and causes them to shorten.
B. Auxin accumulates in cells on the side of the plant facing the source of light and stimulates their elongation.
C. Auxin accumulates in cells on the side of the plant opposite the source of light and causes them to shorten.
D. Auxin accumulates in cells on the side of the plant opposite the source of light and stimulates their elongation.