Answer:
The new solution has a higher concentration than the isotonic saline solution
Explanation:
Here, we want to deduce what has happened in the question.
We are told that the level of the isotonic saline solution dropped because it was connected an unknown solution using a semipermeable membrane.
Since the level of the solution dropped, then it must have occurred that there has been the loss of some of the molecules of the solution.
What has occurred is the process of Osmosis
Osmosis simply involves a movement through a semipermeable membrane of solvent molecules due to the fact that the previous solution is of lower concentration than the present one.
So what we can see here is that there has been a movement due to osmosis as a result of the fact that the new solution has a higher concentration than the former one