According to the Geological survey, water with less than 1000 ml/litre of total dissolved solids is __________.

(a) Brine water

(b) Freshwater

(c) Slightly saline

(d) Moderately saline

(b) Freshwater

According to the U.S. Geological Survey (USGS) water salinity classification, water with less than 1,000 milligrams per litre (mg/L) of total dissolved solids (TDS) is defined as freshwater.

The full classification is as follows:

• Freshwater: Less than 1,000 mg/L
• Slightly saline: 1,000 to 3,000 mg/L
• Moderately saline: 3,000 to 10,000 mg/L
• Very saline: 10,000 to 35,000 mg/L
• Brine water: More than 35,000 mg/L