c) vertical shift of 1 unit down
Given the parent function of a linear equation expressed as:
[tex]f(x)=x[/tex]If the function is shifted vertically downwards by k units, the resulting function will be;
[tex]f(x)=x-k[/tex]Comparing this vertical shift rultewith the resulting function f(x) = x - 1, you can see that the function f(x) = x is shifted vertically down by 1 unit to produce f(x) = x -1.