Hi Worship
Let me try please to explain the issues you have mentioned and then we can ask for expert guidance on this .
For the 1st question — this is an example of comparison. The sentence compares the effect of humidity , air pollution and noise on the children of Maria with the children of her neighbours.
But if we look a little closely and try to understand the meaning of the sentence given in option B , we
Will find that the comparison is not valid as there is no pronoun antecedent for children and thus it wrongly compares children with neighbours.
Whenever we try comparing two entities we should look always for the comparison of apples to apples i.e. we can check if there is any noun in the preceding clause and that it correctly compares with the noun in the succeeding clause .
For the 2nd example , according to
Egmat approach , we should always go with the meaning of the original question sentence and then see if we have any errors grammatically and logically .
So If we take this example we see in option D there is a contrast but it option E the contrast is lost as no contrast word is present and this changes the intended meaning of the original sentence . So better to stick by the meaning given in the original sentence and then see the grammatical and logical correctness.
Hope this helps

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