**Core Concept**
Simple Random Sampling (SRS) is a method of selecting a subset of individuals from a population in such a way that every individual in the population has an equal chance of being selected.

**Why the Correct Answer is Right**
In SRS, each member of the population is assigned a unique identifier or number, and a random selection of these identifiers is made to form the sample. This ensures that every individual in the population has an equal probability of being selected, which is a fundamental principle of statistical inference. SRS is used to reduce bias and ensure that the sample is representative of the population.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not specify the equal probability of selection, which is a key characteristic of SRS.

**Option B:** This option is incorrect as it implies that SRS is a method of selecting a sample based on a specific characteristic, rather than randomly.

**Option C:** This option is incorrect as it suggests that SRS is a method of selecting a sample based on convenience, rather than randomly.

**Clinical Pearl / High-Yield Fact**
A key benefit of SRS is that it allows researchers to make inferences about the population based on the sample, with a known level of precision and confidence.

**Correct Answer: B.**