Answer :
The correct answer is - sampling and coverage.
The survey is not only done by small number of people but that also done by incumbent candidates only, which means the result of the survey is not authentic and genuine.
Problems in Survey
- The major problem in the survey is that the respondents of the survey are self selected and thus it is not sure you will be getting genuine results.
- Inflexible design of the survey is also an issue because of which a lot of people can drop from it and sometimes people do not genuinely answer the survey which affects the results.
To learn more about survey, visit - https://brainly.com/question/17373064
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