How is left-hand rotation indicated for a Hartzell HC-B3M propeller blade?

For a Hartzell HC-B3M propeller blade, left-hand rotation is indicated by specific designations within the propeller's model number, typically within the hub or blade model designations. However, in this case, there are no indications in either the last position of the hub model designation or the blade model designation that specify left-hand rotation as a convention.

The letter "L" is not utilized to denote left-hand rotation in those model numbers, which means that it doesn't appear as suggested in the options provided. Therefore, the correct understanding of the designations leads to the conclusion that neither the hub model nor the blade model contains this information. The indication of rotation is not found in the other designations as specified, leading to the conclusion that the answer is to affirm that neither A nor B is correct.

This highlights the importance of familiarizing yourself with specific manufacturer conventions and nomenclature in aviation maintenance and propeller identification, as they can vary between manufacturers.