Mahua Moita won Bengal’s Krishnanagar Lok Sabha seat in the 2019 election (File). New Delhi: Trinamool leader Mahua Moitra must overcome the challenge of Bharatiya Janata Party debutant Amrita Roy, the matriarch of a local royal family, if she is to win back the Krishnanagar Lok Sabha seat from which she was so controversially expelled last year.  Rajmata (or Queen Mother) Amrita Roy was named Sunday in the BJP’s fifth list, which included quite a few surprises; actors Kangana Ranaut and Arun Govil will contest Himachal Pradesh’s Mandi and Uttar Pradesh’s Meerut, while Varun Gandhi has been dropped from UP’s Pilibhit. Mahua Moitra, 49, eased to victory in Krishnanagar in the 2019 Lok Sabha election, picking up 45 per cent of the votes to finish over 60,000 ahead of the BJP’s Kalyan Chaubey.  Since then, the former investment banker has grown into one of the BJP’s fiercest critics, with impassioned speeches in Parliament, backed up by sharply worded jabs on social media, earning her run-ins with union ministers, saffron party leaders, and right-wing trolls. Krishnanagar has been …