Can you help match these math words with their definitions

Words: voluntary-response, systematic, random, stratified, convenience

Definitions: by chance

members choose to be in the sample

according to a rule or formula

at random from randomly chosen subgroups

easiest to reach

by chance- random

members choose---- voluntary response

according to----systematic

at random-----stratified

easiest to reach----convenience

Random - by chance
Voluntary-response - members choose to be in the sample
Systematic - according to a rule or formula
Stratified - at random from randomly chosen subgroups
Convenience - easiest to reach