Final answer:
The factor least likely to increase the bargaining power of buyers is when switching costs are high, as this makes it expensive or inconvenient for buyers to change suppliers.
Step-by-step explanation:
The factor least likely to increase the bargaining power of buyers is when switching costs are high. High switching costs imply that it is expensive or inconvenient for buyers to switch from one product to another, which decreases their ability to negotiate for better prices or terms. In contrast, the ability of buyers to integrate backward, standardized products or purchase terms, and purchases representing a large percentage of the buyer's costs are factors that generally increase the bargaining power of buyers.
When buyers have the ability to integrate backward into the supply chain by producing the product themselves, they have more leverage over suppliers. Similarly, when products or purchase terms are standard across the industry, buyers can easily find alternative suppliers, which increases their negotiating power. Also, when the purchases represent a large percentage of the buyer's costs, they are more likely to seek and have the leverage to negotiate better terms.
Factors affecting bargaining power are particularly relevant in discussions of international trade, where market dynamics, including the number of competitors, product differentiation, market entry barriers, and competition strategies, can greatly influence both buyers' and sellers' positions in the market.