Final answer:
The blend mode group that ignores black is the Lighten group, which includes modes designed to only blend lighter pixels from layers and would leave black pixels unchanged.
Step-by-step explanation:
The blend mode group that ignores black is b) Lighten. Blend modes in digital art and graphic design software like Photoshop determine how two layers blend with each other to create a certain effect. The Lighten group includes modes like Screen and Lighten, which will essentially ignore black pixels and only blend the lighter pixels from the layers. For example, if you have a layer filled with black and you use a Lighten blend mode with a colorful layer on top, the black will appear unchanged because it's already the darkest color and cannot be lightened further by the blend.