Which type of water source is derived from rainfall and surface runoff?

• A. Groundwater
• B. Surface water
• C. Well water
• D. Desalinated water

Answer: (B)

Surface water is derived from rainfall and surface runoff because it encompasses all bodies of water found on the Earth's surface. This includes rivers, lakes, streams, and reservoirs, which are replenished by precipitation and the movement of water over land. When rain falls, some of it flows over the ground and collects in these bodies of water; this is what we refer to as surface runoff.

Groundwater comes from water that has infiltrated into the ground and fills the spaces in soil and rock, which is different from surface water that remains above ground. Well water is extracted from underground aquifers, also distinct from surface sources. Desalinated water is treated to remove salt from seawater or brackish water, not derived from natural rainfall or surface runoff. Thus, surface water is the most accurate choice for identifying water sourced from rainfall and surface runoff.