Introduction:
Polling is a process of collecting information by asking questions to a sample of individuals. Polling agencies are responsible for conducting these surveys to gain insights into the opinions and attitudes of people towards a particular topic.

The Process:
To interview 200 people, the polling agency would follow the below steps:

1. Defining the Target Population: The polling agency would first define the target population they want to survey. For instance, if the survey is about a political candidate, the target population would be eligible voters in a specific area.

2. Sampling: The polling agency would then create a sample of the target population. A sample is a subset of the entire population that represents the views of the population as a whole. In this case, the agency would randomly select 200 people from the target population.

3. Questionnaire Design: The polling agency would then design a questionnaire to collect data from the sample. The questionnaire would contain questions related to the topic being surveyed, and the questions would be framed in a way that is easy to understand by the respondents.

4. Data Collection: The polling agency would then conduct the survey by either conducting face-to-face interviews, phone interviews, or online surveys. The mode of data collection would depend on the preferences of the respondents and the budget of the polling agency.

5. Data Analysis: Once the data is collected, the polling agency would then analyze the data to gain insights into the opinions and attitudes of the people towards the topic being surveyed. The agency would use statistical techniques to analyze the data and draw conclusions.

Conclusion:
In conclusion, polling agencies play a vital role in gathering information about the views and opinions of people towards a particular topic. The process of conducting a survey involves defining the target population, sampling, questionnaire design, data collection, and data analysis. By following this process, polling agencies can provide valuable insights into the public's opinions and attitudes towards a particular topic.