When every member of a population is put into some order and we choose an arbitrary starting point and select every nth member to be in the sample it is called:

Correct option is B

In systematic random sampling, all members of the population are arranged in some logical order (such as alphabetically, geographically, or by ID number).
An arbitrary starting point is chosen, and then every nth unit is selected until the desired sample size is achieved.
For example, in a population of 1,000 individuals, if a sample of 100 is needed, every 10th person may be chosen after a random start.
Cluster sampling (a) divides the population into clusters and randomly selects entire clusters for study.
Stratified sampling (c) divides the population into strata (e.g., age, gender) and takes random samples from each stratum.
Simple random sampling (d) selects individuals purely by chance without a fixed interval.
Thus, the correct answer is Option (b) – Systematic random sample.