Let X = {a,b,c} and Y = {1,2,3,4}. Using the attached arrow diagram to define a function f from X to Y, what is the range of f?

Let X={a,b,c} and Y={1,2,3,4}. Using the attached arrow diagram to define a function f from X to Y, what is the range of f ? range of f={a,b,c} range of f={1,2,3,4} range of f={1,3} range of f={2,4}