A grab sample is defined as a single sample taken at a specific time.

• A. Composite Sample
• B. Laboratory Sample
• C. Grab Sample
• D. None of the Above

Answer: (C)

Grab sampling captures a snapshot of conditions at a single moment in time. It involves taking one sample from a specific location at a particular time, which is exactly what the statement describes. This is in contrast to a composite sample, which combines multiple samples taken over a period or from different locations to produce an average value. A laboratory sample isn’t about how the sample is taken; it refers to what happens to the sample in the lab, not the collection method. Therefore, the term that fits the definition is the one describing a single, instantaneous sample.