The examples matched with the correct term;
Overcrowding, bad traffic, and high prices - Push factors
Steady work, clean areas, and good schools: - Pull factors
When people willingly choose to leave their homeland - Voluntary migration
When people move to a new location and help others move there as well - Chain Migration
Push factors are conditions which drive people to leave their homes. Examples of push factors can include overcrowding, high prices, unemployment and insecurity.
Pull factors are conditions which attract people to migrate to a particular area. Examples of pull factors include: Steady work, clean areas, good schools, religious freedom and environmental safety.