U.P. Science Congress was organised from 2nd to 4th March, 2013 at

The correct answer is D (D. D. U. Gorakhpur University, Gorakhpur). The U.P. Science Congress is an annual event, run by the U.P. Academy of Sciences with state institutions as hosts, and the venue rotates among the state's universities. The 2013 edition was hosted at DDU Gorakhpur University, which is the answer to this question.

Why the others are wrong, in terms of venue rather than rules:

• A (BHU, Varanasi): BHU is a central university and a frequent host of science events, but it was not the 2013 venue.
• B (Lucknow University): Lucknow hosts many state-level academic events, but this congress was not held there in 2013.
• C (Rohilkhand University, Bareilly): A state university in western UP, not the 2013 host.

The core concept is the institutional architecture of science promotion in UP: state academies, councils such as UPCST, and rotating host universities. For Mains GS-III (science and technology, indigenous R&D), this shows how state-level science policy reaches universities and students.

Trap: Candidates pick BHU or Lucknow because they are the most famous names. Prelims often reward recall of specific event venues, so memorise the host for each year rather than guessing the most prominent university.