A researcher claims that more than 8 0 % of adults in a city own a smartphone. To test this claim, a random sample of 500 adults is selected, and it is found that 4 20 of them own a smartphone. Determine if there is evidence to support the researcher's claim at a significance level of 0.01 . What population parameter is of interest for this problem?
( A )
( B ) rho
( C ) σ
( D ) hatrho