The amount of dissolved oxygen- this water quality indicator should be used to determine the acidity level of the river water which get contaminated by the discharge of waste water.
Option: B
Explanation:
Industrial effluents contaminated river water. If a industry located in the bank of the river then all its waste water will go in the river water and will pollute the fresh water. To judge the water quality of river there are several indicators but the amount of dissolved oxygen is the best indicator.
Like eutrophication refers to the rising up of phosphate level of the water which decreases the dissolved oxygen level which is harmful for aquatic life. If the dissolved oxygen level disturbed then biological oxygen demand of the water will increase and will adversely affect aquatic life.
3% of hospitalized patients in the 2015 survey had one or more HAI.There were an estimated 687.000 HAIs in U.S acute care hospitals in 2015.About 72,000 hospital patients with HAIs died during their hospitalizations.