Q.3- What are keywords? A. These are names given to variables, constants, classes and
methods.
B. These are constants that hold a fixed value of any of the data types.
C. These are special symbols that perform specific operations,
D. These are reserved words that have special meaning in java
language​

These are reserved words that have special meaning in java  language​

Explanation:

Literally, keywords are special words that have special meaning and purpose and can not be used from any other purpose aside from its predefined purpose.

In other words, they are reserved words.

Examples are: public, class, String, int, and many more

Hence, option (d) is correct

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