You should be able to hold down the option key and pick the boot up system you want. If this is something you don't want to happen, go to System Preferences - startup disk and select the operating system you want. If I wanted to get clean, I'd back up using Time Machine to an external drive. Then do as Sterling suggests.
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You should be able to hold down the option key and pick the boot up system you want. If this is something you don't want to happen, go to System Preferences - startup disk and select the operating system you want. If I wanted to get clean, I'd back up using Time Machine to an external drive. Then do as Sterling suggests. I would also try booting into Safe Mode by holding down the Shift key when stating up.
You should be able to hold down the option key and pick the boot up system you want. If this is something you don't want to happen, go to System Preferences - startup disk and select the operating system you want. If I wanted to get clean, I'd back up using Time Machine to an external drive. Then do as Sterling suggests.