Answer:
Option: 2 is the correct answer.
2. the denominator of a probability.
Explanation:
We know that the branches in a tree diagram represent the possible outcome.Tree diagram is specifically used to represent the total number of outcomes that could be possible in an event.
Hence, the total number of branches are the total number of outcomes.
Hence, it denote the denominator of a probability.
( Since the probability is calculated as ratio of number of favorable outcomes to the total number of outcomes.
Hence, the denominator is total number of outcomes )