Allow for the identification of many toxins in a small amount of time.
O1) Confirmation tests
O 2) Positive tests
O3) Negative tests
O4) Screening tests

O4) Screening tests

Explanation:

The screening test is used to make early detection of diseases in order to apply effective treatments. For example, a screening blood test enables the identification of toxins and/or drugs in the patient's system in a relatively low amount of time (generally 24 hours). This bioassay is used for the toxin determination of the effluent sample (i.e., a sample collected and analyzed to evaluate system performance) to the tested species. The screening test generally consists of applying two treatments (i.e., one effluent sample and one control).

i believe the correct answer is d

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.