Concept:Pushkar Fair is a famous annual cattle fair and pilgrimage held in the town of Pushkar, located in the Ajmer district of Rajasthan.Explanation:The fair is also called Pushkar Camel Fair or Kartik Mela. It is one of India’s largest camel, horse, and cattle fairs. Thousands of traders and pilgrims gather here every year. The fair includes cultural events, competitions, and religious rituals at Pushkar Lake. The town of Pushkar lies in the Ajmer district of Rajasthan. Thus, the Pushkar Fair is held in the city of Ajmer.Answer:D. Ajmer