Concept:The error is in part (b), where the passive verb form “has been made” is incorrectly used instead of the active form “has made”.
Explanation:The sentence describes an action performed by the subject “wind power”, so the active voice is required.
The correct structure for active voice is: Subject + main verb + object.
Here, “wind power” is the subject, “made” is the main verb, and “steady progress” is the object.
Using “has been made” changes the sentence to passive voice, which is contextually and grammatically incorrect.
Therefore, part (b) should be “wind power too has made steady progress”.
No errors exist in parts (a) and (c).
Answer:The correct response is option (b).