Read the opening paragraph of the Mantis essay. The praying mantis is a member of the Mantid group of insects. Mantids come in many shapes and sizes and are found all over the world. Some have patterns on their bodies that help them look like the ground. Some are bright green to blend in with leaves and plants. One special mantis is bright pink and looks like an orchid. The mantis is such a strange and engaging creature that many people keep them as pets. For many reasons, mantids have fascinated humans for many years.

Which sentence most clearly introduces the main idea of the essay?

A. Mantids come in many shapes and sizes and are found all over the world.
B. Some have patterns on their bodies that help them look like the ground.
C. One special mantis is bright pink and looks like an orchid.
D. For many reasons, mantids have fascinated humans for many years.