A House Plant That Has Been Placed in the Window

Multiple Choice

A house plant that has been placed in the window will grow toward the source of light because auxin ____.

A) becomes more concentrated on the illuminated side of the plant
B) becomes less concentrated on the illuminated side of the plant
C) becomes more concentrated in the roots of the plant
D) inhibits the growth of cells on the shady side, so the cells on the sunny side grow faster
E) is produced only when the sun shines