In these questions, a part of the sentence is given in bold. Below are given alternatives to the bold part at 1, 2 and 3 which may improve the sentence. Choose the correct alternative. In case no improvement is needed your answer is (4).
Birds sit on the boughs of trees in my garden and with their sweet notes fill the air with music.

Options

A. fill their sweet notes in the air
B. by their sweet notes fill the air
C. fill the air by their sweet notes
D. No Improvement

Answer

C

Explanation

The basic sentence structure is as follows :

Hence, fill the air by their sweet notes is the right usage.