Answer:
Internal databases.
Explanation:
An internal databse is the collection of electronic information obtained from data sources within the company.
Sources of internal data includes records of sales, costs, production schedules, customer, etc.
Internal data bases usually can be accessed more quickly and cheaply than other information sources.
Some disadvantages are:
-information may be incomplete or wrong for making marketing decisions.
-data ages quickly, therefore updating the data base could require major effort.
-managing large amounts of information may require highly sophisticated equipment and techniques.
