Question $19(3$ points$)$

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

$$ superior customer service.

availability of complements.

economies of scale.

low$-$cost input factors.