Determine whether the following statement is true or false, and explain why.

For each commodity produced, the various units needed are entries in a column of the input$-$output matrix.

Choose the correct answer below.

A$.$ True, the units needed are columns in the input$-$output matrix.

B$.$ False, the units needed are columns in the input$-$output matrix.

C$.$ False, the units needed are rows in the input$-$output matrix.

D$.$ True, the units needed are rows in the input$-$output matrix.