Task: Question Answering
Input (English): Problem: a box contains 100 pairs of shoes ( 200 shoes in total ). if two shoes are selected at random, what it is the probability that they are matching shoes ?
Options: a. 1 / 190, b. 1 / 20, c. 1 / 199, d. 1 / 10, e. 1 / 9
Output (English): c