This is a Parallel Reasoning question that involves conditional statements.
Structure: The first sentence contains two premises, and the final sentence is the conclusion.
Diagrams: "Wherever" is a sufficient condition indicator, so we know the first statement should be diagrammed as follows:
Indifferent to the environment-->Pollution is a problem
The second statement also uses "wherever" to indicate the sufficient. Also, we can link it up to the first statement because if pollution is a problem, that implies there is pollution.
Indifferent to the environment-->Pollution is a problem-->harm nature's balance
We should recognize this allows us to infer: Indifferent to the environment-->harm nature's balance
This is exactly what our conclusion is saying, so this is a valid argument.
Attack the Question: Now, we need to keep in mind what we are looking for. We need an answer that closely matches the reasoning technique being used. It can be useful to replace the concepts with letters so that you can get an overall feel for the structure. Here is what the correct answer should look like:
Premises: A-->B-->C
Conclusion: A-->C
A is the correct answer. Here's why:
(A) Premise: Dessert with chocolate-->high in calories-->fattening
Conclusion: Dessert with chocolate-->fattening
This matches the exact same structure and is the correct answer
(B) Premise: Dessert with chocolate-->high in calories
Premise 2: Fattening dessert-->high in calories
...And here is our problem. Notice how we cannot form a chain here. In order for this to be correct, we would need something that links up AFTER "high in calories"
Conclusion: Dessert with chocolate-->fattening
In addition to the problem with the premises, this would require us to reverse the second premise, which would make this a flawed argument. We need the argument to be valid, because our original argument is.
(C) Premise: Dessert high in calories-->chocolate
Premise 2: High in calories-->fattening
Conclusion: Dessert with chocolate-->fattening
Again, we are unable to chain these two conditionals together. Similar issue as B.
This doesn't follow the A-->B-->C structure
(D) Premise: Dessert with chocolate--> high in calories-->fattening
So far so good! This matches the A-->B-->C structure.
Conclusion: Fattening dessert-->chocolate
Here is our problem. This is reversing the direction of the arrow, which is a logical flaw. In order for this to be correct, it would need to say: Dessert with chocolate--> Fattening
(E) Premise: Dessert with chocolate-->High in calories
Premise 2: High in calories <-S-> Fattening
Right away, this is a problem because it is trying to link up a quantifier statement ('many') with a conditional. Our initial argument deals with linking up conditional statements.
Finally, our conclusion is also making a 'many' statement when we want a conditional inference.