Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 345)

Selecting the AF Method
1.
Press the < > button.
2.
Select the AF method.
Each time you press the < > button, the AF method changes.
Note
You can also make your selection from [ : AF method ].
The following descriptions apply to the camera with AF operation set to [ One-Shot
AF ] ( ). With [ Servo AF ] ( ) set, the AF point will turn blue when focus is
achieved.
345