Complex statistical and mathematical theory is an approach, which is classified as

arbitrage pricing theory
arbitrage risk theory
arbitrage dividend theory
arbitrage market theory

The correct answer is: A. arbitrage pricing theory.

Arbitrage pricing theory (APT) is a general equilibrium asset pricing model that states that the expected return of a security is determined by a number of factors, including the risk-free rate, the market risk premium, and the beta of the security. APT is a more general model than the capital asset pricing model (CAPM), which only considers the risk-free rate and the beta of the security.

B. arbitrage risk theory is a theory that states that the risk of an asset is determined by the potential for arbitrage opportunities. An arbitrage opportunity is a situation in which an investor can buy an asset and sell it at a higher price, or vice versa.

C. arbitrage dividend theory is a theory that states that the value of a stock is determined by the present value of its future dividends.

D. arbitrage market theory is a theory that states that the market is efficient and that prices reflect all available information.