Which best explains why the following sentence presents a secularist sentiment?

The city-state of Venice should only be governed by merchants who understand business and not by Catholic clergy who only understand the Bible.

A. Knights and other vassals grew much wealthier than European kings.
B. International trade became more important to European economies.
C. European manufactured goods became more valuable than Asian products.
D. Huge empires replaced European city-states in order to better regulate trade.