Tom, i hope you don't me jumping in. PPT was never really designed for quizzing as such and Pete's advice is bang on. There are 2 aspects to think about - quizzing and the results/analysis. At the moment I am creating courses for approx 1700 learners, the questions have been created in Storyline 3 and the courses containing these have been uploaded to our LMS (BlackBoard) as Scorm files. When learners complete these courses and quiz questions the results are recorded in grade centre.
Now dependng on these results I have set up conditions on our LMS and if a user meets them i.e. more than 50% then BlackBoard provides a completion certificate for the user. If you have smaller numbers of learners then you may be able to provide the lessons without an LMS but for larger scale courses an LMS is essential to manage the users, record scores, produce reports/certs and to meet audit/compliance regulations from your organisation or other parties.