$2.$ Stockholders of Dogs R Us Pet Supply expect a $12\%$ rate of return on their stock. Management has consistently been generating an ROE of $15\%$ over the last $5$ years but now believes that ROE will be $11\%$ for the next $5$ years. Given this, the firm's optimal dividend payout ratio is now $\_\_\_\_\_\_\_\_\_\_.(1$ point$)$

a$.0\%$

b$.100\%$

c$.$ between $0\%$ and $50\%$

d$.$ between $50\%$ and $100\%$