Select the most appropriate option to fill in the blank.
Day by day pollution ______ a serious problem in Delhi.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. is becoming.
Context: The sentence refers to a continuous and progressive action happening day by day in the present.
Meaning of the words:
Is becoming: Present continuous tense — correct form for ongoing change.
Become: Base form — incorrect without auxiliary.
Becoming: Verb form without auxiliary — grammatically incomplete.
Have become: Present perfect — implies completion, which doesn't fit "day by day".
Correct word: Is becoming
Reason: “Day by day” implies gradual ongoing change, so the present continuous tense is appropriate.
Final Sentence: Day by day pollution is becoming a serious problem in Delhi.
Hence, the chosen option is correct.