Among the animal on the planet, the species rich group making more th…

The correct answer is Option (3) → Insects

Option (1) Fishes — Incorrect. Fishes are a small share; even fishes, amphibians, reptiles and mammals together have fewer species than fungi.

Option (2) Mammals — Incorrect. Mammals are among the smallest vertebrate groups in number of species.

Option (3) Insects — Correct. Of all the animals recorded on the planet, insects are the most species-rich group, making up more than 70 per cent of the total. Out of every 10 animals, 7 are insects.

Option (4) Reptiles — Incorrect. Reptiles too are a small group compared with insects.

NCERT Extract:
Biodiversity – “… Let us look at some interesting aspects about earth’s biodiversity based on the currently available species inventories. More than 70 per cent of all the species recorded are animals, while plants (including algae, fungi, bryophytes, gymnosperms and angiosperms) comprise no more than 22 per cent of the total. Among animals, insects are the most species-rich taxonomic group, making up more than 70 per cent of the total. That means, out of every 10 animals on this planet, 7 are insects.”