Which best describes the location and role of the lymphatic system?

The lymphatic system is a network of vessels and tissues located throughout the body, parallel to the circulatory system. It plays a crucial role in maintaining fluid balance by collecting excess interstitial fluid and returning it to the bloodstream. Additionally, it is integral to the immune system, as it transports lymph, which contains lymphocytes and other immune cells, helping to defend against infections and diseases. Key components include lymph nodes, lymphatic vessels, and organs such as the spleen and thymus.