Question

1. what is the error in this sentence? \to improve his results, the experiment was repeated by the scientist.\

the modifier is misplaced.

there is no error.

the modifier is dangling.

the sentence is a fragment.

Explanation:

A dangling modifier occurs when the modifier (here, "To improve his results") does not clearly modify the intended subject. The phrase "To improve his results" implies the one doing the action (improving results by repeating the experiment) should be the subject, but the subject of the main clause is "the experiment" (which can't perform the action of improving results). A misplaced modifier is about incorrect placement (not the case here), the sentence is complete (not a fragment), and there is an error (so "no error" is wrong). So the error is a dangling modifier.

Answer:

The modifier is dangling.