Final answer:
Registrars are the organizations that have relationships with the .org TLD zone manager to enable domain registration. They are accredited by ICANN and work with the registry that manages the TLDs, whereas IANA maintains the DNS root zone.
Step-by-step explanation:
The registrars are the types of organizations that have relationships with the .org TLD zone manager allowing domain registration. A registrar is accredited by the Internet Corporation for Assigned Names and Numbers (ICANN), which is the organization responsible for managing the internet's domain name system. They have agreements with the registry, which is the entity that manages the specific TLD (Top-Level Domain) and maintains the database of domain names registered in that TLD. The Internet Assigned Numbers Authority (IANA) is involved in the delegation and maintenance of the DNS root zone but does not directly manage relationships with registrars for TLDs.