If a researcher selects every n^th element from a list of population elements to be included in his sample, which of the following types of sampling technique is he using?

Systematic random sampling involves a systematic method of selecting every nth number in the population to be a member of the sample, although the first member of the sample may be selected by simple random method. Since every member of the population has an equal chance of being selected into the sample, the technique is considered as systematic as well as random.