Organized interest groups enhance american democracy by
a. fielding large numbers of electable candidates.
b. financing large numbers of election campaigns.
c. empowering less potent segments of society.
d. representing the interests of large numbers of people and encouraging political participation.
e. placing initiatives on the ballot.

D. representing the interests of large numbers of people and encouraging political participation

Explanation:

Even though interest group often have a bad reputation due to their power to control government officials with their monetary donation, it actually a great medium to encourage political participation among citizens.

Citizens who have a same principles could form their own interest group and help to promote government officials that represent the same principle as them.