Question

At ground level, nitrous oxides are bad enough, but when up high, atmospherically they bond with free ions to create dangerous smog particles.

• A. but when up high, atmospherically they
• B. however, it is in the upper atmosphere
• C. but in the upper atmosphere, they
• D. they however, but once in the upper atmosphere it is known to
• E. as in the upper atmosphere they

Hint:

Ensure smooth transitions between clauses by maintaining clarity and avoiding unnecessary words.

Answer 1

The Correct Option is C

Step 1: Understand sentence flow.
The sentence needs to clearly describe the transition from ground level to the upper atmosphere without creating confusion. Option (C) is the best choice.
Step 2: Review the options.
- (A) "But when up high, atmospherically they" is awkward and not clear.
- (B) "However, it is in the upper atmosphere" introduces unnecessary complexity.
- (C) "But in the upper atmosphere, they" is the clearest and most grammatically correct choice.
- (D) The phrasing is awkward and introduces unnecessary complexity.
- (E) This option is grammatically incorrect and unclear.
Conclusion:
Option (C) is the best because it maintains clarity and proper sentence structure.