The seeds of certain plants fail to germinate if they do not pass through the digestive tract of fruit-eating birds. This is due to - (1) hibernation (2) seed coat impermeability (3) infertility (4) vegetative reproduction
(2) seed coat impermeability Explanation: A dormant seed is one that is unable to germinate in a specified period of time under a combination of environmental factors that are normally suitable for the germination of the non-dormant seed. Dormancy is a mechanism to prevent germination during unsuitable ecological conditions, but the probability of seedling survival is low.