Answer: Systematic sampling
Step-by-step explanation:
Systematic sampling is a method when sample members from a population are selected based on a random starting point but in this case, there's a fixed, periodic interval.
It involves the selection of every kth case from the population given. Since the researcher extracts information about hospital readmissions from a population of 6,000 client records and samples every 20th record from the population, beginning with record number 5, then this is a systematic sampling.
