Final answer:
An Oracle 12c keyword is a word that has a predefined meaning in the Oracle 12c database system. These keywords are reserved and cannot be used as object or column names in SQL statements.
Step-by-step explanation:
An Oracle 12c keyword is a word that has a predefined meaning in the Oracle 12c database system. These keywords are reserved and cannot be used as object or column names in SQL statements. Examples of Oracle 12c keywords include SELECT, FROM, and WHERE.
The correct answer to the question is D) keywords. In Oracle 12c, the term keywords refers to words that have predefined meanings and cannot be used as regular identifiers.
It is important to be aware of these keywords when writing SQL queries in Oracle 12c, as attempting to use them as object or column names will result in syntax errors.