The core concept tested here is understanding the purpose of a standalone media property in the context of marketing strategies. The correct answer is C, as BabyCenter is designed to promote not only Johnson & Johnson's products but also complementary and even competitive products. This strategy enhances the site's objectivity and provides companies with opportunities to learn valuable information about appealing customer appeals. Option A is incorrect because BabyCenter does not exclusively sell Johnson & Johnson products. Option B is misleading as the primary purpose is not just to provide unbiased information but to promote products. Option D is incorrect because the main goal is not direct competition but rather promotion and information sharing.