Step 1: Understand what an access specifier is.
An access specifier controls the visibility or accessibility of classes, methods, variables, and constructors in object-oriented programming. It decides from where a member can be accessed.
Step 2: Recall the common access specifiers in Java.
In Java, the commonly used access specifiers are:
- public -- accessible from everywhere.
- private -- accessible only within the same class.
- protected -- accessible within the same package and also in subclasses.
- default -- when no access specifier is written, it is called default or package-private access.
Step 3: Compare the given options.
- (A) private: This is a valid access specifier.
- (B) protected: This is also a valid access specifier.
- (C) package: This is not an actual keyword used as an access specifier. The correct term is default access or package-private access, but package itself is not an access specifier keyword.
- (D) public: This is a valid access specifier.
Step 4: Conclusion.
Therefore, the option which is \underline{NOT} an access specifier is
package.
Final Answer:package.