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

Pruning makes the hedge plant dense because

Most of the information regarding auxins has been obtained from

The Avena curvature test is used for the bioassay of which of the following?

Storage sprouting of potato tubers can be prevented by treatment with low concentrations of

$A$: If a plant is kept horizontally,auxin accumulates on the lower surface.
$R$: Displacement of statoliths and other cell organelles to the lower surface modifies the translocation pattern of auxin.