Which of the following best describes convenience sampling?

Convenience sampling is best described as obtaining a sample that is easily accessible. This method involves selecting individuals who are readily available to the researcher, rather than using a random selection process. This approach is often used in research when quick data collection is needed or when resources are limited. The primary advantage of convenience sampling is that it allows researchers to gather information from a population without the constraints of time and cost associated with more rigorous sampling methods.

While the other options mention techniques that might be used in different sampling strategies, they do not fit the definition of convenience sampling. Random selection would involve a systematic way of ensuring each individual has an equal chance of being selected, while choosing individuals based on their knowledge suggests a purposive sampling method, focusing on specific criteria. Finally, assigning participants without criteria does not align with any structured sampling process and lacks the intent of collecting a representative sample for research. Therefore, option A accurately captures the essence of convenience sampling within the context of research methodology.