Question: Which of the following sentences is incorrectly structured in terms of voice?

Options:

1. The song was sung by the choir.
2. The choir sings the song.
3. The song is sung by the choir.
4. The choir was sung by the song.

Correct Answer: The choir was sung by the song.

Solution:

In this sentence, \'the choir\' cannot be acted upon by \'the song\', making it incorrect.