Last year, the results of a survey at one college suggested that 21% of students smoked regularly. This year, after an intensive college-wide anti-smoking campaign, a researcher wishes to investigate whether the proportion of smokers has changed. Let p represent the proportion of students who smoke regularly today. State hypotheses for a significance test, letting the alternative hypothesis reflect the possibility that the proportion of students who smoke today is larger from the proportion last year. O a. Ho: P 21% Ob. Ho: P=21% Ha: p > 21% O c. Ho: P=21% Ha: P * 21% O d. Ho: P 21% Ha: p= 21%