In Azure AD Conditional Access policy there is a Grant access. When more controls are checked, are all of them required or is just one of them required?do all requirements need to be matched or is one of

It depends on how the "For multiple controls" option is set.

• Require all the selected controls
• Require one of the selected controls 

In the first case, all the selected controls are required, in the second one any of the selected controls is enough.