Which type of periodic table uses A and B designations for main groups and transition metals?

The designation of A and B groups in the periodic table is specifically associated with the North American Convention Periodic Table. This system classifies the main group elements, which are denoted by the 'A' designation, and the transition metals, which are denoted by the 'B' designation. This classification helps to easily identify and group elements that have similar properties and behaviors.

In contrast, the IUPAC Periodic Table uses a numbering system from 1 to 18 to label groups, making it distinct from the designation system that employs A and B. The European Convention also aligns more closely with the IUPAC system and does not utilize the traditional A and B group labeling. The Traditional Periodic Table, while historical, does not specifically categorize groups in the same way as the North American Convention. Thus, the North American Convention is the correct answer as it directly relates to the A and B designations for grouping elements in the periodic table.