Chrysanthemums are short-day plants that normally flower in late fall. Suppose you were a chrysanthemum grower and you would like to produce a chrysanthemum crop for harvesting around Mother's Day (the second Sunday in May). Assuming you live in the temperate Northern Hemisphere, which of the following strategies would work to accomplish your goal.

Option D

Explanation:

Options for the question

A)import seeds produced in the southern hemisphere.

B)plant the flowers out-of doors in november.

C)keep the plants in a warm growing environment.

D)expose the plants to an hour of light in the middle of each night until the end of april.

Solution

Since Chrysanthemum is a short-day plant, its flower mainly develop during night and hence they require long nights of 11 to 12 hours. Blackout system is sometimes used to induce flowering.Flowering can be delayed by regulating both light and temperature. this is done by exposing plants for a short period of time to light (can be artificial) and to some source of heat that produces 85° F or higher temperature.  

Thus if flowers are required in month of may, flowering can be delayed by exposing Chrysanthemums plant to light and heat source during night time

Option D is correct

the answer is sex-linked recessive.