which statement can be inferred about the speed of sound and freshwater and in seawater

Question

Both temperature and salinity decrease the speed of sound in water.
At 80°C, the speed of sound in freshwater and seawater will be the same.
The speed of sound increases as the density of water increases.
The speed of sound increases as the salinity of water decreases.

Answer 1

Both temperature and salinity decrease the speed of sound in water.