Which of the following is not a classification of matter a. periods b. groups c. columns d. families

I mean technically none of them are really labels for matter itself, they're just labels for how things are grouped on the Periodic Table of Elements.

But I would say C. Columns.

The rows are called periods and the columns are called groups or families when talking about the Periodic Table, but the actual terms rows or columns shouldn't be used.

Herbivores, carnivores, omnivores, decomposers, herbivores

It’s the energy source of stars