In autumn, many trees shed their leaves and change their color. which explains the reason for this behavior? . . a. in autumn, the amount of ethylene decreases, rendering the cells of the abscission layer more sensitive to auxin.. b. in autumn, the amount of auxin decreases, rendering the cells of the abscission layer more sensitive to ethylene.. c. in autumn, the amount of gibberellins decreases, rendering the cells of the abscission layer more sensitive to auxin..

B.In autumn, the amount of auxin decreases, rendering the cells of the abscission layer more sensitive to ethylene..

Explanation:

The Ethylene and auxin are two hormones that are present on plants, fruits and vegetables, Ethylene accelerates fruist and vegetables maduration, but decreases growth in leafs and trees, and Auxin is in charge of sending the singals to the leafs and trees to grow, so when autum comes auxin decreases so the leafs stop receiving signals to grow, and they become more sensitive to ethylene which make them grow slower and eventually die.

at the bottom

explanation: