Which of the Following Was a Source of Strength for the Sasanian

Which of the following was a source of strength for the Sasanian Empire under Khusro I Anoshirwan?

A) The long era of peace that he established,allowing trade and agriculture to develop
B) Religious conformity with the Sasanian empire
C) Control of the Silk Roads and other land routes between East Asia and the Mediterranean region
D) Control of sea lanes in the Indian Ocean to dominate trade between East Asia and the Mediterranean