Final answer:
To find the probability that Adam and Ella will be selected from the chess club, we identify there is one favorable pair and a total of 10 possible pairs, resulting in a probability of 1/10 or option B.
Step-by-step explanation:
The question asks about the probability that Adam and Ella will be the two students selected from a chess club with 5 members to participate in a tournament. To find this, we calculate the total number of possible pairs and the number of favorable outcomes. There is only one pair that includes Adam and Ella. To determine the total number of pairs we can form from 5 members, we use the combination formula C(n, k) = n! / (k!(n - k)!), where n is the total number of items to choose from, and k is the number of items to pick.
The total number of ways to pick 2 members from 5 is C(5, 2), which is 5! / (2!(5 - 2)!) = 10. Therefore, the probability Adam and Ella will be selected is 1/10 since there is one favorable outcome out of 10 possible pairs. The correct answer is option B.