The correct options are
B The British would control the Malwa regions.
C Ranjit Singh's empire's boundary would be Satluj.
The British and Ranjit Singh had friendly relations in 1805-06. But when Ranjit Singh attacked the Satluj multiple times in the following years, the British interfered. In 1809, Maharaja Ranjit Singh and the British signed the Treaty of Amritsar, according to which, Satluj was to be the boundary, and the British would control the Malwa regions.