The vertical bar down the right side of the DSO is where the major mode and menu buttons are located.
The set of buttons that appear depend on the type of BitScope you're connected to and the major mode currently selected. For example, when connected to a BS220S the available buttons in ALT mode are:
POWER and SETUP are always present. The buttons below these are the major mode selectors. In this case the choice is ALT, CHOP and MIXED. Below these are the display types which in the case of ALT are A/B and ADD. Other display types include X/Y, MIXED and LOGIC displays, FFT and spectrum displays and more.