Which organisms are labelled as primary consumers?

The correct answer is Option (1) → Herbivores

Animals cannot make their own food, so they are called consumers (heterotrophs). Those that feed on producers, the plants, are the primary consumers. So the primary consumers are the herbivores. Animals that eat these herbivores are secondary consumers.

NCERT Extract:
Energy Flow – “… All animals depend on plants (directly or indirectly) for their food needs. They are hence called consumers and also heterotrophs. If they feed on the producers, the plants, they are called primary consumers, and if the animals eat other animals which in turn eat the plants (or their produce) they are called secondary consumers. Likewise, you could have tertiary consumers too. Obviously the primary consumers will be herbivores.”