What is a data broker?
a. a business that collects personal information about consumers and sells that information to other organizations.
b. a storage repository that holds a vast amount of raw data in its original format until the business needs it.
c. a technique for establishing a match, or balance, between the source data and the target data warehouse.
d. an approach to business governance that values decisions that can be backed up with verifiable data.

The correct option is a.

A business that collects personal information about consumers and sells that information to other organizations.

Explanation:

Data brokers, also known as data suppliers, data fetchers, information brokers, or even data providers are businesses or companies (even individuals) that, on the most basic level, source and aggregate data and information (mostly information that are meant to be confidential or that are in the real sense difficult to get) and then resell them to third parties. These third parties could be other data brokers.  

They collect data and information from a wide range of resources and sources - offline and/or online e.g web access history, bank details, credit card information, official records (such as birth and marriage certificates, driver's licenses).  

Brokers can steal round about any information. Examples of information that brokers legally or illegally steal are full name, residential address, marital status, age, gender, national identification number, bank verification number. Brokers and hackers are siblings.

A couple types of data brokers are:

1. Those for fraud detection

2. Those for risk mitigation  

Hope this helps!