Final answer:
Theoretical probability is used for simple experiments with defined sample spaces and equally likely outcomes. It's calculated by dividing the number of favorable outcomes by the total number of possible outcomes. The correct option is c. Theoretical probability.
Step-by-step explanation:
The type of probability used in relatively simple experiments with easily defined sample spaces is theoretical probability. Theoretical probability is based on the principle that all outcomes in the sample space are equally likely to occur. To calculate the theoretical probability of an event A, one counts the number of outcomes that make up event A and divides it by the total number of outcomes in the sample space.
For instance, if one wants to determine the probability of rolling a four on a fair six-sided die, there is only one outcome that produces a four, and there are six possible outcomes in total. Thus, the theoretical probability of rolling a four is 1/6. This method is used when the outcomes are clearly defined, and each outcome has an equal chance of occurring. Therefore, the correct option for this question is c. Theoretical probability.