The above answer is completely incorrect. Please do not choose a. as your answer.
I believe this question is multiple choice, since I have it on Odessyware and it has checkboxes indicating that more than one answer can be chosen. In this case the answer is easy to find, since the Pax Mongolica is the time on Mongolian peace. This means that Mongolia starting a war with the Japanese or conquering the Vikings are both out of the question since neither action is peaceful. Promoting interstate relations and making trade and travel safe, however, are peaceful actions. So if you can select more than one answer, the answers will be b. promoted interstate relations and d. made travel safer. If you can only choose one, go with d. made travel safer.
