Forward I’m heavy, backward I’m not.

What am ?

It depends on what type of third separates the three notes.for example: if you have two mayor thirds is an "aumented chord"if you have two minor thirds is an "diminued chord"if you have one mayor first and then one minor is a "mayor chord"and inverted is a "minor chord"

Iwould go with a or d would be your answer

Hey user  he  bachs contributions to the baroque period were bassed of keyed instruments