Read these paragraphs and answer the question that follows:

in 2008, more than one million american students gave nearly 20 million service hours to their communities. they made a difference in people's lives and learned some important life lessons in the process. organizations, including schools, are actively promoting service for all citizens as a way to be involved, others, and improve themselves.

service is other people and being active in your community. for example, one group of teens planted a community garden with their friends. they grow a variety of vegetables. the garden requires regular care. the teens donate the produce to a local soup kitchen. workers there use the produce to feed people in the community. by tending the garden and donating their produce, the teens are actively make life a bit better for others in their community.

service is valuable in ways that cannot be measured in dollars. people volunteer or serve others without expecting money or gifts in return. service is not about earning money. it is not just collecting money to give to a group. it is about action and contributing to the common good. the people who serve as well as those who receive benefit in many ways that are more important than money or gifts. for example, a soup kitchen provides essential food to people who may otherwise go hungry. the soup kitchen is extremely valuable for those struggling to get enough to eat. those serving learn about compassion and how others can improve life for all.

millions of americans are making society better for themselves and for others. they are participating citizens in their community, raising up those who are less fortunate. in return, they become better people who can understand the perspectives and needs of others, which are invaluable and important qualities of good citizens.
which sentence best represents the main idea of paragraph three, the second body paragraph?