Animals and plants must have a habitat or home, ________ is comfortable and clean, and ________ there is enough food and other resources.

1. A.
   that; where
2. B.
   which;不填
3. C.
   which; where
4. D.
   that;不填

Animals and plants must have a habitat or home, ________ is comfortable and clean, and ________ there is enough food and other resources.

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