Bachelor of Arts (BA) (Hons.) in Urdu is a three year Under Graduate (UG) program in Urdu language offered by various colleges and universities across the country. Students who have passed their class 12th or equivalent examination from a recognized state or central board can make an application for the course provided that they satisfy other eligibility criteria listed by the respective college or university.
Some of the colleges that offer BA (Hons.) in Urdu

Zakir Husain College, Delhi
Aligarh Muslim University, Aligarh
ANS College, Patna
Bokaro Steel City College
DAV College, Bihar
Doranda College, Ranchi
There is no condition for taking BA hons in Urdu language other than candidates must have completed their 12th. So it doesn't matter whether you have taken science. You can still pursue.
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