The internal growth rate of a firm is best described as:$$ A$.$ The maximum growth rate achievable without external financing of any kind. B$.$ The maximum growth rate achievable without using any external equity financing, while maintaining a constant debt$-$equity ratio. C$.$ The maximum growth rate achievable without any limits on the amount of debt financing used.O D$.$ The minimum growth rate achievable if the firm maintains a constant equity multiplier. E$.$ The minimum growth rate achievable if the firm does not pay out any cash dividends.