According to the passage, which of the following is true about recent studies of the gender gap in the United States politics? A. They accurately depict voter preference in the South prior to 1980. B. They have been unduly influenced by changes in voter preferences. C. They fail to recognize important factors affecting levels of voter participation. D. They do not pay sufficient attention to the effect regional differences have on voter preference. E. They are more concerned with the choices that male and female voters make than with the frequency with which they vote.