Question

click the ____________ to accept the extrusion options in the properties box. green checkmark red \x\ mark ok button insert extrude feature button

Explanation:

In many software interfaces, the green checkmark is used to confirm and accept options. The red "X" is for canceling, the OK button is usually for general - confirmation in dialogs but not always the specific way to accept extrusion options, and the insert extrude feature button is for adding the extrusion feature rather than accepting options.

Answer:

Green checkmark