What is the action spectrum of photoperiodism?

In some plants,the cold treatment may be replaced by the application of

The site of perception of light in plants for flowering is

Some plants like sugarbeet and cabbage require low temperature for flowering. This phenomenon is called:

Which of the following statements are $INCORRECT$ with respect to phytochrome?
$i$. Phytochrome is a light-receiving proteinaceous pigment present in the leaves of plants.
$ii$. Phytochrome pigment exists in two forms.
$iii$. Two forms of phytochromes are interconvertible.
$iv$. Phytochromes are located in the chloroplast of green cells.
$v$. Phytochrome $P_r$ form inhibits flowering in $LDP$ during the dark period.

Which of the following pigments absorbs red and far-red light?