<prompt> True morbidity in a population can be calculated bySentinel SurveillancePassive SurveillanceActive SurveillanceMonitoring  <response>: Active Surveillance Extra measures are taken to collect data and confirm diagnoses to ensure more complete repos for surveys and outbreak investigations. Active surveillance encompasses formal and informal communications. Eg: Malaria surveillance by a health worker Main objectives of Surveillance 1. Provide information about new and changing trends in the health status of population - morbidity, moality, nutritional status 2. Provide feedback 3. Provide timely warning Ref: Parks Textbook of Preventive and Social Medicine; 24th edition - Page no. 45 