ব্যাখ্যা
সঠিক উত্তর: (ক) to
"Obstacle to" — The Fixed Collocation in English Grammar:
"Obstacle" সর্বদা "to" preposition-এর সাথে ব্যবহৃত হয়।
Structure: obstacle + to + noun/gerund
Meaning: যা কিছু অগ্রগতিতে বাধা দেয়
Examples:
— "Ignorance is an obstacle to progress." ✓
— "Poverty is the main obstacle to education."
— "Fear is often an obstacle to success."
Similar Collocations with "to":
— barrier to, hindrance to, impediment to, threat to
— key to, solution to, answer to, challenge to
Why others are wrong:
✗ "obstacle for" — not a standard collocation
✗ "obstacle with" — incorrect; "with" expresses accompaniment, not opposition
✗ "obstacle from" — incorrect; "from" implies origin/separation, not the right sense here
Mnemonic:
Think of "obstacle" as a wall blocking your PATH TO somewhere — the path goes "to" the goal, and the obstacle blocks it. So → obstacle TO progress.
Source: Oxford Collocations Dictionary; Practical English Usage — Michael Swan; NTRCA Question Bank.