In basic probability, which of the following values cannot be a probability of an event?

• A. $0$
• B. $1$
• C. $0.35$
• D. $1.2$

Answer: (D)

Verified step by step guidance

1. Recall the fundamental property of probability: the probability of any event must be a number between 0 and 1, inclusive. This means \(0 \leq P(E) \leq 1\) for any event \(E\).
2. Understand that a probability of 0 means the event is impossible, and a probability of 1 means the event is certain to occur.
3. Probabilities can take any value between 0 and 1, including decimals like 0.35, which represents a 35% chance of the event occurring.
4. Identify that any value less than 0 or greater than 1 cannot be a valid probability because it violates the basic probability rule.
5. Therefore, among the given values, 1.2 is not a valid probability since it is greater than 1.