The correct option is D All of the above
Under the unfavorable condition, seeds stop metabolic activity and undergo the inactive or resting stage is called as seed dormancy. Seed dormancy can be caused by various factors such as temperature, light, water, permeability of the seed coat, hormones like ABA and external inhibitors. Dormancy prevents germination during unsuitable ecological conditions when the probability of seedling survival is low.
Thus, the correct answer is option D.