Forts

Shivaji’s forces used hill forts, local knowledge, surprise attacks, rapid movement and withdrawal to challenge larger armies. This style is commonly described as guerrilla warfare and suited the rugged geography of the western Deccan. It was not based only on slow open-field battles, stopping trade or issuing paper currency, so the combination in A is correct.

Forts gave the Marathas secure bases for storing supplies, governing territory, protecting routes and launching military operations. Hill forts were especially valuable because their difficult terrain slowed larger forces and supported the use of mobile warfare. Although forts could have several functions, their main strategic importance was defence and control, making A correct.