Answer:
a) calculating the concentration at which 50% of the test organisms of a particular species die
Explanation:
Bioassays -
<u>Bioassays is an analytical method to assess the effect of marine pollutant on the organism by estimating the concentration at which 50% of the test organisms die after exposing the test organisms for a specified time.</u>
It can be done by quantitative or by qualitative experiment , or direct or indirect .
It is used to detect the biological hazards or give the quality assessment of the mixture .
It is also used for the monitoring the quality of water .
