Answer:
A.-1 is the constant term
Constant term of an algebraic expression: A term of an algebraic expression which has a fixed numerical value in all situations and does not have any variable is called the constant term of an algebraic expression.
For examples, in the algebraic expression 5x + 2y + xy + 10, 10 is the constant term of the expression. therefore from the above algebraic expression 2x²+x-1, -1 will be the constant term