What evidence supports McWhorter's claim that he 'would have felt more comfortable in the past'? (Select all that apply.)
a. The linguistic landscape in America was prissier in the past than it is now.
b. In the past, educated people, both black and white, used language more formally than uneducated ones.
c. In the past, blacks did not have the expectation that all people of their color would speak in the same way.
d. In the past, language used in public was more formal; casual speech was reserved for use with family and intimate friends.