Chrome book short cuts

Which one is open file? Options: Ctrl + R, Ctrl + P, Ctrl + O

What is this function being displayed? Options: Bookmark, Screenshot, Partial Screenshot

Which one is cut image/text? Options: Ctrl + X, Ctrl + Y, Ctrl + Z

Which one is print? Options: Ctrl + R, Ctrl + F, Ctrl + P

Which one is close tab? Options: Ctrl + A, Ctrl + W, Ctrl + X

Which one is bold? Options: Ctrl + B, Ctrl + A, Ctrl + O

Which one is zoom in? Options: Ctrl + +, Ctrl + -, Ctrl + A

Which one lock? Options: Ctrl + Shift + L, Ctrl + A, Ctrl + U

Which one is reload screen? Options: Ctrl + R, Ctrl + O, Ctrl + B