Correct answer: A. Ability to project power and commercial influence across the seas
Explanation: The direct answer is A: Rajendra Chola I's naval policy shows the ability to project power and commercial influence across the seas. A navy requires ships, sailors, ports, supplies, organization, and the ability to conduct expeditions far from the mainland. Rajendra Chola I's naval campaigns, including activity toward Southeast Asia, demonstrate that the Chola state could use maritime power to protect or extend political and commercial influence. Option A is correct. Option B is wrong because it limits the evidence to mountain defence, which does not explain naval campaigns. Option C is wrong because desert warfare is unrelated to a maritime policy. Option D is wrong because tax writing alone cannot explain ships or overseas expeditions. Memory cue: Chola naval campaigns mean sea power, overseas reach, and trade influence.