Tendrils exhibit/twining of tendrils is due to

Pick out the correct statements.
$I.$ Cytokinins especially help in delaying senescence.
$II.$ Auxins are involved in regulating apical dominance.
$III.$ Ethylene is especially useful in enhancing seed germination.
$IV.$ Gibberellins are responsible for immature falling of leaves.

Wound hormone is called

Which of the following is a plant hormone?

Study the following statements.
$I.$ "$X$" hormone promotes root growth and root hair formation, thus helping the plants to increase their absorption surface.
$II.$ "$Y$" hormone induces flowering in mango and also promotes rapid internode/petiole elongation in deep-water plants, hence helping leaves or upper parts of the shoot remain above water.
$III.$ "$Z$" hormone inhibits seed germination, increases the tolerance of plants to various stresses, and plays an important role in seed development, maturation, and dormancy.
Identify the correct names of hormones marked as $X$, $Y$, and $Z$.

Plants are killed in winter by frost because: