The correct option is B Lucknow
The fourth edition of India International Science Festival (IISF) was held at Lucknow, Uttar Pradesh. The 1st IISF was held at IIT New Delhi in December 2015. The mega S&T expo attracted more than 3 lakh people. India had also set a Guinness Book of World Records when 2000 school students performed two experiments at the Festival. The 2nd Festival at CSIR-National Physical Laboratory, New Delhi in December 2016 showcased Indian achievements in various fields of science and technology. The third in the series was held in October 2017 in Chennai.