Option #2: No, her sample is not an appropriate, random sample. It does not represent the whole population.
While the student is testing ice samples from coffee drinks, the sample might not be representative of all ice used at the coffee shop. The selection process for the drinks may not ensure that all variations of ice (e.g., different times of day, different drinks, etc.) are included, which could introduce bias. Additionally, if the samples are taken only from coffee drinks without considering other drinks that may use the same ice, this further limits the generalizability of the findings. For a thorough examination of ice cleanliness, a more systematic approach to sampling that includes a wider range of factors would be necessary.