A researcher studying social media usage among teenagers obtains an alphabetical list of all 600 students at a local school. They choose a random starting number between 1 and 20, which is 12, and select the 12th12^{\text{th}}12th student on the list, followed by every 20th20^{\text{th}}20th student thereafter (the 32nd32^{\text{nd}}32nd, 52nd52^{\text{nd}}52nd, 72nd72^{\text{nd}}72nd, and so on) until they have a sample of 30 students. Which sampling technique is the researcher using?
Random sampling
Stratified sampling
Systematic sampling
Volunteer sampling
644 exam-style questions on OCR A Level Psychology Research methods and techniques. Each one has a worked solution and a mark scheme showing where the marks go.