Lucknow, Oct 5 : Nearly 50 per cent of the candidates opted out of the Union Public Service Commission (UPSC) preliminary examination 2020 for selection to Indian Administrative and Allied Services in Lucknow. The exam was conducted on Sunday. According to sources, as many as 43,921 candidates were registered for the examination at various centres in the city. About 21,790 (49.6 per cent) registered candidates appeared in the first shift for "general studies" paper. The number dropped further to 21,607 (49.2 per cent) in the second shift for "optional subject". This was a sharp drop as compared to 15-20 per cent average dropout seen in previous years. The majority of the students, who had dropped out of the examination, cited Covid-19 pandemic as the main reason for the high number of absentees. The candidates said that apart from the fear of catching an infection, many of them could not prepare for the test because of restrictions on coaching classes, group studies, library sessions and mentorship programmes in the past six months. "Besides lack of preparedness, there was a risk of catching Covid-19 infection, which made many of my batchmates skip the examination," said Niharika Rastogi, a candidate. /IANS