The correct option is B Sankaranarayanan
Medieval Kerala had gained much progress in the field of knowledge. Sankaranarayana was a famous astronomer during the reign of 'Perumals'. He has authored Sankaranarayaneeyam, a book on Astronomy. The contributions of Samgrama Madhavan to Mathematics gained worldwide acclaim. Ashtanga hridayam on Ayurveda was also written during this period.