Final answer:
The Pew Research Center survey's mean age of 69 most likely corresponds to the 'ages 65 and older' group, as this is the demographic group that encompasses the age 69.
Step-by-step explanation:
Based on the information provided, the mean age of 69 does not directly correlate with the age groups listed in the Pew Research Center survey from 2009. However, considering the listed age groups and the statistic in question, the most likely group to have a mean age of 69 would correspond to respondents who are part of the 'ages 65 and older' group. This is based on standard demographic distributions where the mean age of a population group is most likely to fall within that group. In the list of age groups, 'ages 65 and older' broadly covers all ages above 65, making it plausible that the average age within this group could be 69.