Which auxin should be used to eradicate dicotyledonous weeds from a monocotyledonous crop field?

Identify the functions of auxin and choose the correct option.
$I.$ Initiate rooting in stem cuttings
$II.$ Promote flowering in pineapples
$III.$ Controls xylem differentiation

The fruits and leaves fall before maturity in the absence of:

Which member of the auxin group is widely used to kill dicotyledonous weeds?

Which of the following is $NOT$ an effect of $Auxin$?

Low concentration of auxin lowers the growth of