MANAGEMENT

Detailed explanation-1: -Secondary data means data collected by someone else earlier. Surveys, observations, experiments, questionnaire, personal interview, etc. Government publications, websites, books, journal articles, internal records etc.

Detailed explanation-2: -Sources of secondary data include books, personal sources, journals, newspapers, websitess, government records etc. Secondary data are known to be readily available compared to that of primary data. It requires very little research and needs for manpower to use these sources.

Detailed explanation-3: -So the one which is not a source of secondary data is (D), questionnaires. This is a source of primary data.

Detailed explanation-4: -Secondary data consist of information that has already been gathered and might be relevant to the problem at hand. Primary data, in contrast, are survey, observation, and experiment data collected to solve a particular problem.