Correct option is D
According to
USGS and IPCC:
·
68–69% of global freshwater is locked in
glaciers & ice caps.
· Only ~1% is available as surface/groundwater.
Why other options are wrong
· (a) 2% is too low.
· (b) 10% not supported by hydrological data.
· (c) 50% still below actual value.