Answer:
Systematic sampling
Explanation:
The 'Systematic sampling' method is described as the sampling technique in which the researchers aim to zero down a specific population as per their target size they want to research on. Thus, the entire population is divided by the desired size of the sample(manager selecting 300 workers from 3000 workers) and selecting the sample from this target sample at a fixed interval(every 10th name). It is an easy and convenient sampling method in comparison to the random method of sampling which makes it more conducive in an area with a wide population. Thus, it exemplifies 'systematic sampling.'