Selecting and deleting multiple notes

I am trying to separate two choral voices on a single staff. To do so I have duplicated the staves and deleted one part for each leaving the staves with SATB voicing. To delete the tenor and alto pars fro the basss and soprano staffs (staves .... right?) required that I depress the CTRL key while selecting the not.es I want to delete (highlighting them in the process) an hit the delete button, There must be a way to simultaneously select multiple note so that they are highlighted. What is that mechanism?