Select the incorrect option regarding vernalization.

What is the action spectrum of photoperiodism?

When all parts except the leaves of a short-day plant are covered with a light-proof cover and then subjected to short-day light/dark treatment,it will produce flower buds. When a portion of this plant is grafted onto another plant of the same species which has been prevented from flowering by excessive exposure to light,this latter plant will also produce flower buds. Which is the best inference from this result?

Subjecting the growing of which plant to a cold treatment stimulates subsequent photoperiodic flowering response?

On germination,a seed first produces shoots with leaves,and flowers appear later.
$(A)$ Why do you think this happens?
$(B)$ How is this advantageous to the plant?

The pigment phytochrome is involved in: