Answer: Technically, depending on other unstated variables, the answer could be much larger/smaller (and numbers not stated in the answer), but assuming the question asked how many handshakes are possible in a group of 11 people where each of the people must shake each other's hands once and only once, the answer would be "C."
Step-by-step explanation:
Because of all the possible combinations with the stated condition (where each of the people must shake each other's hands once and only once), it can be concluded that there are 110 possible handshakes to be done with each other.
Picture this, one person going around shaking each others person one-at-a-time. A person would shake ten other people's hands, and the same thing done with the rest 10 people.
1 person shaking hands with 10 other people = 10 hands shaked
10 people shaking hands with 10 other people = 100 hands shaked
Adding this up, you get 110 hands shaked.
