You can set the default approval statuses that are available to your reviewer when they are within the Review Application. The Approved as Is and Not Relevant options are required to be available (every project must have a status selected before it can be returned)
Setting Default Approval Statuses
Go to the MyAccount>Customize>Approval Statuses menu, and check which options you require to be displayed or hidden from your reviewers.
When your reviewer(s) access their content, they will have your default options to choose from to approve their project.