Choose the appropriate preposition: She persevered _____ her studies and graduated near the top of her class.

• Persevere (at/in/with):
English Meaning- To persist in a state, enterprise, or undertaking in spite of counter influences, opposition, or discouragement.
Bengali Meaning- অধ্যবসায়ী হওয়া; নিরবচ্ছিন্ন মনোযোগে কাজ করে যাওয়া। 
- নিরবিচ্ছিন্নভাবে কোন কাজ করে যাওয়া বুঝাতে 'Persevere in' ব্যবহৃত হয়। 
Example:
- She persevered in her studies and graduated near the top of her class.
- He persevered in his idea despite obvious objections raised by friends. 

Source: 
1. A Passage to the English Language by S.M. Zakir Hussain. 
2. Accessible Dictionary by Bangla Academy.