The Carhart Four-Factor Model

Which of the following is consistent with the Carhart four-factor model?

No. This describes a single-factor model such as the CAPM, but not a multifactor model like the Carhart four-factor model.

That's not it. All four factors referred to are independent variables.

Right! An asset's excess return is estimated by modeling the value using four factors, an alpha term, and an error term. These are necessary for estimation, but then they're assumed to be zero in expectation.

Expected returns are explained only by a market premium

The four factors include three independent variables and one dependent variable

The alpha term and the error term in the model are both assumed to be zero in expectation