Please refer to the following paper for question 1-4
Wastewater-based epidemlology (WBE] is an method to estimate the consumption, or population. Chemicalk/pathogen can be excreteod from our bodyr, go through seweages and eventualy to the wastewater treetment r exposure to chemicals/pathogen in a plants. Therefore, by meas; asuring the concentrations of chemicals/ pathogen in wastewaters and through the back- calculation, the total usage or exposure can be estimated. WBE has commonly being used to monitor illicit drug use in the communities and has also recently being used for COVID-19. 
1.(10%) What type of water pollutant is COVID-19?
(A) Infectious agents
(B) Organic chemicals
(C) Inorganic chemicals
(D)Radioactive materials