The correct answer is: C. relational, arithmetic, assignment

In the absence of parentheses, the order of evaluation of operators in an expression is as follows:

  1. Relational operators (<, >, <=, >=, ==, !=)
  2. Arithmetic operators (+, -, *, /, %)
  3. Assignment operators (=)

For example, in the expression a = b + c, the + operator will be evaluated first, then the = operator.

Here is a table that summarizes the order of evaluation of operators in expressions:

| Operator | Precedence | |---|---| | Relational operators | 1 | | Arithmetic operators | 2 | | Assignment operators | 3 |

Note that the order of evaluation of operators can be changed by using parentheses. For example, in the expression (a + b) = c, the + operator will be evaluated before the = operator.