Primary and secondary treatment of wastewater leads to _______.a.High BODb.Increase in DOc.Low BOD and CODd.High COD

The primary and secondary treatment of wastewater leads to c. Low BOD and COD.

Here's why:

Primary treatment of wastewater involves the removal of large and small particles from the wastewater. This is usually achieved through the use of screens and sedimentation processes.

Secondary treatment involves the use of biological processes to further purify the wastewater. This usually involves the use of bacteria to break down organic matter in the wastewater.

Both of these processes help to reduce the Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) in the wastewater. BOD is a measure of the amount of oxygen that bacteria will consume while breaking down organic matter. COD is a measure of the total amount of oxygen that would be consumed if all the organic matter in the water was oxidized.

Therefore, primary and secondary treatment of wastewater leads to a reduction in both BOD and COD, making option c the correct answer.