The risk-free rate, average returns, standard deviations, and betas for three funds and the S&P 500 are given below:

Fund	Average returns	Standard deviations	Betas
A	21%	30%	1.4
B	30%	40%	1.2
C	18%	20%	0.8
S&P 500	15%	20%	1
rf	2%

a. What is the Treynor measure for portfolio A?

b. What is the M² measure for portfolio B?

c. If these portfolios are subcomponents that make up part of a well-diversified portfolio, then portfolio _______ is preferred.