The . . . . . . . . allows you to abbreviate an assignment statement.

The correct answer is: B. Shorthand operator

A shorthand operator is an operator that allows you to abbreviate an assignment statement. For example, the assignment statement x = y + z can be abbreviated as x += z.

The other options are incorrect because:

• An arithmetic assignment operator is an operator that performs an arithmetic operation and assigns the result to a variable. For example, the arithmetic assignment operator += adds the value of the right-hand operand to the value of the left-hand operand and assigns the result to the left-hand operand.
• A long operator is an operator that performs a long operation. For example, the long operator strlen() returns the length of a string.
• A predefined operator is an operator that is defined by the programming language. For example, the predefined operator + adds two numbers.