The correct answer is “Harisena”.
Harisena wrote the Harshacharita, which is a biography of Harshavardhana. This book provides valuable information about the time period.
Rājataraṅgiṇī is a metrical legendary and historical chronicle of the north-western part of Indian sub-continent, particularly the kings of Kashmir. It was written in Sanskrit by Kashmiri historian Kalhana in the 12th century CE.
Kalidasa lived during the reign of Chandragupta II (Vikramaditya), the Gupta king who ruled from 375–415 CE.