For a poorly diversified portfolio the appropriate measure of portfolio performance would be

a. the Sharpe measure because it uses beta as the risk measure.

b. the Jensen measure because it measures the risk-adjusted performance.

c. the Sharpe measure because it evaluates portfolio performance on the basis of return and diversification.

d. the Treynor measure because it evaluates portfolio performance on the basis of return and diversification.

e. the Treynor measure because it uses standard deviation as the risk measure.