IANA has primarily been responsible with assigning address blocks to five regional internet registries (RIR). A tech needs to research address blocks assigned in the United States. Which RIR should the tech contact?

Q: IANA has primarily been responsible with assigning address blocks to five regional internet registries (RIR). A tech needs to research address blocks assigned in the United States. Which RIR should the tech contact?

or

Q: The primary task of IANA has been to allocate address blocks to the five regional internet registries (RIR). A technician must investigate address blocks allotted in the US. The tech should get in touch with which RIR?

• LACNIC
• APNIC
• ARIN 
• RIPE

Explanation: ARIN, which stands for the American Registry for Internet Numbers, should be contacted by the technician. In the United States, they are the most reliable source for handling address assignments.