Let a and B Be Valid Boolean Expressions

Multiple Choice

Let a and b be valid boolean expressions. Which of the following best describes the result of the expression a || b?

A) It will evaluate to true if a evaluates to true and b evaluates to true. It will evaluate to false otherwise.
B) It will evaluate to false if a evaluates to false and b evaluates to false. It will evaluate to true otherwise.
C) It will evaluate to true if a evaluates to false and b evaluates to false. It will evaluate to true otherwise.
D) It will evaluate to true if a evaluates to false or b evaluates to false. It will evaluate to true otherwise.
E) None of the above statements correctly describes the evaluation of the expression.