( A. Numbers. ) ( B . Variables ) ( C . Mathematical operators. ) ( D . A solution ) ….. Thank you for your time and your help ….
It’s D. An expression does not contain a solution. If a solution is present, an Expression becomes an Equation.
Expression: 2x + 3y.
Solution absent, expression.
Equation: 2x + 3y = 10.
Solution there, equation.
it would be mathematical operators
the rest may have a negative sign in front of them.