Step 1: Understanding the question.
The question asks about the ruler who introduced a standardized silver coin system in India. Step 2: Analyzing the options. (A) Akbar: Akbar continued the currency system but did not introduce it. (B) Sher Shah Suri: Correct — He introduced the silver rupee as a standard coin. (C) Alauddin Khilji: He focused on market reforms, not coin standardization. (D) Babur: Babur founded the Mughal Empire but did not introduce silver coins. Step 3: Conclusion.
Silver coins were introduced in India by Sher Shah Suri.