An inspector needs to determine if a facility's wastewater discharge is instantaneously exceeding the daily maximum pH limit as stated in its NPDES permit. Which sampling technique is most appropriate for this specific objective?
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A
A 24-hour flow-proportional composite sample.
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B
A time-weighted composite sample taken over an 8-hour shift.
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C
A grab sample.
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D
A stratified random sample taken from multiple points in the effluent stream.