Matrix question conditions.

I want to have 4 rows, 2 columns and have the answer select 1 in each column, leaving 2 rows without answers. 
I can give these instructions I'd like if the form made it only this option available. 

From what I understand, you want the user to be able to select only one answer in each column? Unfortunately that is not possible for the matrix field. With the radio field, you can only limit the answer per row, not per column.

A possible workaround I could suggest would be to change the input type to Radio Button then interchange the column with the row, so that you have 4 columns and 2 rows.

With this setup, the user can only select one answer for the "Most" row, and one answer for the "Least" row.

Please let us know if you need further assistance.
Regards.