The correct answer is C. By building a huge standing army.
Step-by-step explanation
The Mauryan Empire a great empire of India commanded by the Mauryan dynasty, from about 320 BC. Until about the year 185 a. C, in which they managed to have control of the north, central India, and some regions of other countries such as Pakistan and Afghanistan thanks to the huge army that allowed their expansion and security, avoiding invasions from other Empires. This Empire was characterized by strong internal and external trade, agriculture and economic activities benefited thanks to a unique and efficient system of finance, administration, and security throughout India. According to the above, the correct answer is C. By building a huge standing army.