Identify the sampling method:

(a) TSA agents pull aside every 20th passenger coming through security for enhanced screening.

(b) The IRS selects 8,000 corporate filings of the 225,000 received that year for a potential audit.

(c) A baseball team selects 14 seating sections in the stadium and issues a questionnaire to everyone in those sections.

(d) A football team gives away a bobble-head doll to the first 10,000 fans that enter the gates that day.

(e) A principal selects three students from each first period classroom to form a Home Room Advisory Committee.