Choose the most appropriate option to fill in blank no. 4.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. or.
The sentence suggests that music is something we listen to, and sometimes we even hum or sing along.
The correct conjunction to use here is "or" because it introduces an alternative action — "listen to music or hum or sing."
The other options don’t fit the context.