Answer:
b less concentrated
Explanation:
The molarity of a solution represents the number of moles of solute per volume of the solution. Molarity is one of the ways of measuring the concentration of a solution.
When a solution is diluted, the number of moles of solute in the solution remains the same while the volume of the solution increases. This leads to a lower molarity/concentration.
Hence when a solution is diluted from 5 M to 1 M, it becomes less concentrated.
The correct option is b.