Water will move from a salt solution to a salt solution when they are across a differentially permeable membrane.

The answers are low concentrated (dilute) and high concentrated respectively. 

As the low concentrated salt solution has a higher water potential than that of the high concentrated salt solution, water molecules will flow from the region of higher water potential to the region of lower water potential, thus from the dilute salt solution to the high concentrated salt solution. This is due to the movement called osmosis. Note that osmosis also requires water to flow through a differentially permeable membrane, which means the membrane can allow certain substances (not all) to go in or out. If the differentially permeable membrane is not present, the movement of water molecules may be regarded as diffusion. 

Therefore, the answers for the blanks are low concentrated and high concentrated.

The answer options is d