Final answer:
The statement 'B. There will be some variability in outcomes.' must be true in the long run for probability, as variability is inherent to random processes. Outcomes will distribute according to their probabilities over many trials, known as the law of large numbers.
Step-by-step explanation:
The question addresses the concept of probability and its interpretation in the long run. Specifically, the statement 'B. There will be some variability in outcomes.' must be true in the long run when discussing random events or processes. In probability theory, even when there are a fixed number of trials and the trials are independent and conducted under identical conditions, variability is an inherent part of random processes. Each outcome has a certain probability, but that does not guarantee uniformity in outcomes over multiple trials. Instead, over the long run, there will be a distribution of outcomes reflecting the probabilities of each event.
For example, each toss of a fair coin is independent of the previous one, with a fixed probability of 0.5 for heads and 0.5 for tails. While in the short run it might appear that heads or tails is favored, over a large number of coin tosses, the distribution of heads and tails will reflect their probabilities. This is known as the law of large numbers. However, this does not mean that all outcomes happen equally often; there will be fluctuations, which represent the variability in outcomes.