Observe the following structure. The above structure is of an auxin,which is:

Match the following columns.

Column-$I$	Column-$II$
$A$. Natural auxin	$1$. $IAA$
$B$. Synthetic auxin	$2$. $NAA$
	$3$. $IBA$
	$4$. $2,4-D$

Choose the correct matching sequence.

$A$: $2, 4-D$ is widely used by farmers in agricultural and horticultural practices.
$R$: Flowering in most plants can be initiated by using high concentration of Auxin.

Which hormone is responsible for apical dominance?

The pineapple, which under natural conditions is difficult to blossom, has been made to produce fruits throughout the year by the application of:

Define parthenocarpy. Name the plant hormone used to induce parthenocarpy.