d. The Indus river was completely within the boundaries of the Persian Empire, Alexander's conquests, and Mauryan Empire
Explanation:
The Indus river is located in what it is Pakistan these days. It is the only river that was completely within the boundaries of the Persian Empire which include parts of current Pakistan, Alexander's conquests which included territories from Macedonia until parts of India, and also Mauryan Empire that included parts of current Pakistan up to some parts of current Bangladesh. The river Ganes, Krishna and Brahmaputra were part of the Mauryan Empire however, they are not included in the Persian Empire or of Alexander's conquests.
