Answer:
A. True
Step-by-step explanation:
Dr. Edgar F. Codd was able to generate twelve (12) rules after his research on the Relational Database Model. One of his rules, the second one precisely which is the Guaranteed Access Rule specifies that 'all single database elements or values are most certainly guaranteed to be accessible through a combination of the primary-key model also known as the row value, the attribute-name also designated as the column value and the table-name. The information rule which is the first rule also specifies that all information must be represented as one value in rows and columns.
So, this implies that a single database field should contain multiple data values. He also mentioned that data cannot be accessed through any other means except for the above stated.