Reinstall Yosemite on Macbook Air I have bought Macbook with Lion, which I have upgraded to Yosemite. Now I want to reinstall Yosemite from stratch. Which Mac OS version will be installed if I'll follow this instructions (Command (⌘) and R keys).

Will it install Lion (which was installed on my Mac Air when I have bought it) or will be downloaded last version - Yosemite?

How can I install Yosemite from stratch?
From OS X: About OS X Recovery


  Which version of OS X is installed by OS X Recovery?
  
  
  If you use the Recovery System stored on your startup drive to    reinstall OS X, it installs the most recent version of OS X previously installed on this computer.
  If you use Internet Recovery to reinstall OS X, it installs the version of OS X that originally came with your computer. After installation is finished, use the Mac App Store to install related updates or later versions of OS X that you have previously purchased.
  


So as long as the local Recovery disk partition is intact it will install, at this point in time, OS X Yosemite 10.10.4.