Which of the following factors could reduce trade volumes between countries?

Increased tariffs on imports can significantly reduce trade volumes between countries by making foreign goods more expensive and less competitive in the domestic market. When a country imposes higher tariffs, it creates additional costs for importers, who may pass these costs onto consumers. Consequently, consumers may choose to buy domestically produced goods over more expensive imported ones, leading to a decrease in the overall volume of trade. This protective measure can be used to shield local industries but often results in strained trade relationships and can provoke retaliatory tariffs, further diminishing trade.

In contrast, the other options pertain to factors that typically promote trade or foster collaboration. The exchange of cultural practices can enhance mutual understanding and stimulate demand for each other's goods, while shared technological advancements can lead to improved efficiencies and innovation, encouraging trade. Membership in international trade agreements often reduces tariffs and other barriers, facilitating higher trade volumes between countries. Thus, the introduction of increased tariffs is the factor that directly inhibits trade growth.