Final answer:
The type of sampling used when the friend recorded the calories of sports drinks from his refrigerator is convenience sampling.
Step-by-step explanation:
When your friend recorded the calories of the sports drinks in the refrigerator, the type of sampling conducted was convenience sampling. This is because the sample was taken from an easily accessible source (the refrigerator at home) rather than using a method that ensures that the sample is representative of a larger population. Convenience sampling is a non-probabilistic sampling technique where subjects are selected because of their convenient accessibility and proximity to the researcher.