The first India International Science Festival (IISF) was held in December 2015 at:

Correct option is A

​The correct answer is (a) IIT Delhi.

Explanation:

• The first India International Science Festival (IISF) was held in December 2015 at the CSIR - National Physical Laboratory, New Delhi.
• It was organized to celebrate science and technology and their impact on society and to showcase India's achievements in the field of research and innovation.
• Jointly organized by the Ministry of Science and Technology, Ministry of Earth Sciences, and Vijnana Bharati (VIBHA).

Information about Other Options:

• CSIR - National Physical Laboratory, New Delhi: The second edition of the India International Science Festival (IISF) was held at CSIR-National Physical Laboratory (NPL) in New Delhi from December 7–11, 2016, under the theme "Science for the Masses". 
• IIT Guwahati: The 10th India International Science Festival (IISF) was held from November 30 to December 4, 2024, at IIT Guwahati, Assam, under the theme "Transforming India into an S&T-driven Global Manufacturing Hub". 
• Indira Gandhi Pratishthan, Lucknow: The fourth edition of the International Science Festival 2018 was organized in Lucknow under the theme "Science for Transformation".

Information Booster:

• India International Science Festival is a collaborative endeavour between the Ministry of Science and Technology, Ministry of Earth Sciences, Department of Space, and Department of Atomic Energy in partnership with Vijnana Bharati.
  
• The India International Science Festival (IISF) 2025 will be held on January 11–12, 2025 at Fergusson College in Pune.
• The festival's theme is "Ideas to Impact: Science for the People".

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