The correct answer is B because the law of one price can be used to value a derivative security. This principle asserts a one-to-one relationship between the derivative and its underlying asset at maturity, ensuring only one price exists for each derivative.

A is incorrect because derivatives pricing models assume the no-arbitrage condition holds, meaning arbitrage opportunities do not exist during the pricing process.

C is incorrect because the price of the underlying asset is not inferred; instead, it is used as a given input in the calculation of the derivative's price, as demonstrated in the one-period binomial model.