A firm has a beta of $1\mathrm{.}23.$ Which one of the following will increase the WACC of the firm?

Multiple Choice

An increase in the risk$-$free rate of return.

A decrease in the level of risk of a project.

An increase in the marginal tax.

An increase in the debt$-$equity ratio.

A decrease in the yield$-$to$-$maturity of the bonds.