Which transformation from the graph of a function f(x) describes the graph of f(x) -1

Question

O vertical stretch by a factor of 1

O vertical shift down 1 unit

O vertical shift up 1 unit

O horizontal shift left 1 unit

Answer 1

Vertical shift 1 unit down. A number after the function is a vertical translation positive means up and negative means down.

If you had f(x-1) then it's inside the function and it transforms a function right 1 unit. If it were f(x+1) it would transform the function 1 to the left.