Sentence Correction (SC) | The Poison Dart Frog and the Inland Taipan are the most poisonous anim

RonPurewal kindly help in explaining why A is wrong,

I marked option D which is correct answer.
I was also confused between A and D
In A , there was no main verb after animals, - no verb.
On the other hand in D , the sentence is well written with clear verbs and meaning.

Kindly solve this ques for option A and D.

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