Subject to Section 9 hereof, to the extent that the Option has become vested and exercisable with respect to a number of Shares as provided herein, the Option may thereafter be exercised by the Participant, in whole or in part, at any time or from time to time prior to the expiration of the Option as provided herein and in accordance with Sections 7.5 and 7.6 of the Plan. No Shares resulting from the exercise of an Option shall be issued until full payment therefore has been made as set forth in the Plan.