Actually, with so many difference schemes out there to group the elements, the A and B system doesn't work very well as far as communications are concerned. One system in use that uses A and B to place the elements is the exact reverse of another system that uses A and B.
You are correct, the statement is false. The actinides and lanthanides are not elements in group 3A. The actinides are a series of elements located in the f-block of the periodic table, and the lanthanides are a series of elements located in the d-block. Both the actinides and lanthanides have similar chemical and physical properties, but they are not part of group 3A. To verify this, you can refer to the periodic table, which shows the specific group numbers for each element.
