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Answer:</em></h2>
The answer is systematic sampling.
Step-by-step explanation:
A poll was conducted in which out of total 496 students entering the school, every 49th student entering the school was polled.
This is systematic sampling.
Systematic sampling is defined as a sampling method where sample is selected from a large population. These samples are selected with a fixed periodic interval.
Whereas in stratified sampling method, the sample is randomly created out of elements from all the strata.
In the cluster sampling method, the data is divided into groups called clusters. And all the units of these clusters form a sample.
In convenience sampling, the data is collected from people who are conveniently available to participate in polls.
Therefore, as per the definition, we can say that the answer is systematic sampling.