Why is it necessary to conserve endangered species ?

Q.

(this chapters name is ecosystem not population )

how might studying ecosytem help to conserve endangered species?

Q. An international convention regulating trade in endangered species, especially bears and tigers, could be significantly weakened were it not for restrictions on captive breeding of endangered species, warn conservation and animal welfare groups.

A) could be significantly weakened were it not for restrictions on captive breeding of endangered species, warn conservation and animal welfare groups.

B) could be significantly weakened if restrictions on captive breeding of endangered species aren't eased, warn conservation and animal welfare groups.

C) couldn't be significantly weakened without restrictions on captive breeding of endangered species being eased, warn conservation and animal welfare groups.

D) can't be significantly weakened if restrictions on captive breeding of endangered species are eased, warn conservation and animal welfare groups.

E) could be significantly weakened if restrictions on captive breeding of endangered species are eased, warn conservation and animal welfare groups.

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Q. An ex situ conservation method for endangered species is

Q. One of the ex-situ conservation methods for endangered species is