Current Attempt in Progress

Company $B$ has decided to build a customer database for their newly started business of selling concrete to home building companies.

What type of database should they build and what should the primary key be comprised of$?$

Data Mart with a key recorded in audio of the customer's name

Relational database with a key of customer id number

Object$-$oriented database, with a key of address

Data Warehouse with a key of zip code