Answer:
Simple random
Explanation:
There are various methods which may be employed when we intend to select a certain few from a larger group of subjects. The simple random sampling may be described as the most basic form of random sampling whereby a smaller group or subset is chosen from the larger population entirely by chance (each subject or member of the population has equal chances of being selected). A simple random sampling, the larger group isn't partitioned or subdivided prior to selection, the subsets are just selected as they are. In the scenario above, the database is the population and the 50 samples are selected directly from the database without splitting or prior partioning of the population data.