Both BioThink Inc. and GD Pharma Inc. have discovered similar vaccines to prevent cancer. While GD Pharma's vaccine sells at $100 per unit, BioThink sells its vaccine at $90 per unit. This price differentiation has mainly been attributed to the companies' capital decisions. While BioThink used its retained earnings to develop the vaccine, GD Pharma borrowed funds from banks to develop the vaccine. Thus, GD Pharma pays a higher interest on its capital, which makes it necessary to price its vaccine higher. Thus, the key driver for BioThink's competitive advantage is:

Based on the information provided within the question it can be said that BioThink's competitive advantage in this situation would be their very cheap input factors. This refers to any resource that a company uses in order to output a certain product. Therefore by paying less on the resources they use they are then able to price their product cheaper than their competitors, thus giving them a competitive advantage.

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