(Identify the type of sampling method used.) A candidate for the senate creates an automated message that calls every third listed phone number and reminds them to vote for him in the upcoming election. Convenience Sampling
Cluster Sampling
Systematic Sampling
Stratified Sampling

Systematic Sampling

Step-by-step explanation:

Systematic sampling is one of the types of probability sampling method. It is an advanced form of simple random sampling. In this form, from the population of members, sample members are selected randomly. In this random selection, a starting point is fixed. The sample is created when the members are selected from the fixed intervals.  

In the given excerpt, systematic sampling method has been used. Here, the sample has been created by selecting every third listed phone member. The interval has been created between in the sample size.

d is the correct answer

step-by-step explanation:

x= 8 because 3x = 3 * 8, and 3*8 = 24