Here's how you can hide system software updates in the Mac App Store in OS X.
1. Open the Mac App Store.
2. Control-click or right-click a system software update.
3. Click on Hide Update.
4. You can reverse this by clicking on the Store menu and selecting "Show All Software Updates." Be sure to quit and reopen the Mac App Store after doing this to see all system software updates again.
For more, see the original article at the link below.