Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to babyproof windows [title] Lock your windows. [step] Many windows have built-in locks you can latch shut with a key to prevent the window from opening. If your windows have keys built-in, this is your best option for baby proofing your windows.

Ending1: You can even use a lock ring to lock your window. [substeps] Make sure to lock the windows if they will be moving around in windows. Ending2: [substeps] If you have a power panel on your windows that will be installed later, you can lock it now. [title] Install a windows-only unit to ensure baby protection. Ending3: If your windows do not have keys, however, use another method. Installing keys is costly and time-consuming and it's far easier to use an alternative window locking method. Ending4: [substeps] If your windows do not have locks, you do not need to lock them. If the windows have not a lock feature, they can be unlocked with a key.

Answer format: ending1/ending2/ending3/ending4