Osmosis is $..................$

Osmosis can be demonstrated by

Identify the error in the following statement: "Osmosis is the diffusion of water across a semi-permeable membrane between two solutions of different concentrations."

What is correct for osmosis?

Which plant is used for demonstrating plasmolysis in the laboratory?

An onion peel was taken and
$(a)$ placed in salt solution for five minutes.
$(b)$ after that it was placed in distilled water.
When seen under the microscope,what would be observed in $(a)$ and $(b)$?