Which parent function has a constant slope? a. linear b. square root c. quadratic d. exponential

The slope of a line is the tangent of the angle that forms the line with the positive direction of the abscissa axis.
 We note that for linear functions, this value is always the same.
 The standard equation of the line is:
 y = mx + b
 Where,
 m = slope of the line.
 This value is always the same regardless of the domain of the function.
  
 A parent function that has a constant slope is:
 A.linear