Question

read the passage.
the ghost orchid is a subject of fascination among plant experts and enthusiasts alike. this flowering plant has no leaves and relies on its roots to anchor onto tree bark. the roots are well camouflaged, so the ghost orchid seems to hover in the air. this appearance of floating, along with the flowers ghostly white petals, give the plant its name. exclusively located in regions of cuba and south florida, the ghost orchid requires a very specific type of wetland habitat. this rare plant relies on a humid climate, moderate temperatures, filtered sunlight, and the presence of a certain fungus for its survival.
what is the main, or central, idea of the passage?
the ghost orchid gets its name from its ghostly white petals, which allow the plant to camouflage itself in its environment.
the ghost orchid only grows on one type of fungus, which limits the plants ability to expand to other environments.
the ghost orchid, known for its peculiar appearance, depends upon a particular set of conditions in order to grow.
the ghost orchid is a common variety of orchid that is difficult to see because of its use of camouflage.

Explanation:

The passage describes the ghost orchid's unique appearance (floating - like, white petals) and its specific growth requirements (humid climate, certain fungus, etc.). The main idea should encompass both appearance and growth conditions.

Answer:

The ghost orchid, known for its peculiar appearance, depends upon a particular set of conditions in order to grow.