select multiple worksheets by partial name

I have a workbook with worksheets named in the following way, where A, B, and C stand for different words :

A, B, C, A (1), B (1), C (1), A (2), B (2), C (2),...A (52), B (52), C (52)

Sometimes I need to select all the A sheets or all of the B or C sheets to make changes that will apply to all those sheets. So far I have done this by scrolling through the worksheet tabs and CTRL+mouse clicking each tab I want to group. This is tedious and time consuming. May I ask someone to create a macro that will allow me to choose A, B, or C and then will group all of the worksheets that have A, B, or C as the first part of the worksheets' name?

I should mention that worksheet A is not the first worksheet in the workbook. I have three worksheets before A but they do not follow the naming pattern shown above.

Arthur