The correct answer is: A. Asymptotics
Asymptotics are the limiting behavior of a function as its input approaches a particular value. In the case of probability, the asymptotic behavior of the frequency of an event as the number of trials approaches infinity is the probability of the event.
For example, if you flip a coin 10 times, you might get 6 heads and 4 tails. If you flip the coin 100 times, you might get 55 heads and 45 tails. And if you flip the coin 1000 times, you might get 505 heads and 495 tails. As the number of trials increases, the proportion of heads approaches 0.5, which is the probability of getting heads on a single flip of a fair coin.
B. Symptotics is not a word.
C. Asymmetry is not a property of probability.
D. All of the mentioned is not the correct answer.