Experts can i have the answer for the 20 th question

Dear student,                     
​Please find below the solution to the asked query     

​a. Auxin
b. Auxin
c. Gibberellic acid (GA₃)
d. Abscissic Acid
e. Ethylene
f. Gibberellins

Hope this information will clear your doubts about the topic.   
​If you have any more doubts just ask here on the forum and our experts will try to help you out as soon as possible.   Regards