In paragraph 2, the word "it” refers to ____.

A. A fifth of all the birds in the world live in the rainforest.

B. 20% of all the animals in the world live in the rainforest.

C. Nearly two million species of insects are found in the Amazon rainforest.

D. Nearly half of the world's species of plants grow there.

A. reduced considerably

B. put a tick

C. examined carefully

D. motivated to develop

A. chamber

B. flat

C. area

D. studio

A. remove their wax coating

B. kill off bacteria

C. maintain their color

D. crack their skin

A. All people suffer from global warming.

B. All people benefit from global warming.

C. Life is more difficult for the majority of people.

D. Life is easier for most people.

A. predictable

B. unpredictable

C. changeable

D. unchangeable