Consider the Following to Answer the Question(s) Below

Multiple Choice

Consider the following to answer the question(s) below.
KiPLEX manufactures plastic pipes. KiPLEX piping is a less expensive alternative to copper piping. BPLEX's marketing department wants to determine plumbers' satisfaction with KiPLEX piping. To do this, they plan to survey plumbers who purchase KiPLEX pipes on regular basis.
-Suppose that there are five categories of plumbers (individuals, small local businesses, home renovation companies, condo renovation companies, and high rise construction companies) . The marketing specialists decide to randomly select 20 individuals from each category. This sampling method is called

A) simple random.
B) stratified.
C) cluster.
D) systematic.
E) convenience.