According to the basic gravity model, a characteristic that tends to affect the probability of trade existing between any two countries is the distance between them.Colonial and historical ties is also a characteristic that can also affect the probability of trade between any two countries and may help explain the possible differences between the predictions of the basic gravity model and actual trade flows. One of the important implications that we can derive from the gravity model is the pattern and composition of trade between any two countries. Hence, **option(A) i.e only statements (ii) and (iii) are true.**