The target paragraph needs an opening that previews its point and fits the larger draft. Paragraph 1: Residents in remote towns sometimes traveled several hours for routine blood tests, and delayed testing could postpone a clinician's decision about medication or follow-up. Paragraph 2: [Topic sentence needed.] A mobile laboratory visits each town on a published schedule and sends samples to the regional hospital the same day. Local clinics coordinate appointments, while urgent or highly specialized tests still take place at the hospital. Paragraph 3: The service reduces travel for predictable routine testing without presenting a mobile unit as a complete replacement for regional facilities. Which sentence best opens Paragraph 2 by defining the mobile service at the appropriate scope?