After the test, you may cancel your scores immediately after completing the test, while still in the testing room. However, once you request an unofficial score report (immediately after the test), you no longer have the option of canceling your scores. More about GMAT scores:
The MBA dissertation (or thesis in some universities) will, in general, comprise the following in some combination:  a discussion of the literature , providing a critical review and structuring of what is known on a given topic, with a view to addressing a specific problem; a case study that goes beyond simple description, containing the analysis of hitherto unpublished material; a test of the application or limitations of some known principle or technique in a particular situation, and / or suggested modifications. As an alternative to the dissertation, some programs instead allow for a major project.  Here (part-time) students will address a problem current in their organization; particularly in programs with an action learning orientation, these may be practically oriented.  Most MBA programs require additional course work in research methodology, preceding the dissertation or project. Some programs allow that the research component as a whole may be substituted with additional elective coursework.