This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to measure vertical blinds
Go with an inside mount for a cleaner look.
With an inside mount, the blinds sit inside the window or door frame. This allows the blinds to blend in with the window or door for a clean, streamlined look.

Select from the following.
[1]. One feature of the inside mount is that the window is hidden so that the blinds are camouflaged from view. Without the out mount, blinds won't be a significant part of the overall aesthetic of the window or door.
[2]. A no go would be to use an inside mount in a bedroom with closed blinds or in a basement with all of the blinds shut. If you are using an inside mount for bedroom measurements, you can handle this as a simple installation.
[3]. The exterior mount will allow you to control the brightness and contrast between the outside mount and the inside mount. The sides of a window on an outside mount are slightly crowded, making it harder to situate your blinds horizontally.
[4]. Choose an outside mount for a frame without depth. An inside mount requires that the window or door frame has a certain depth in order to fit the the blinds.
The answer is:
[4].