Fencing and Math

Assessment September 2008

The figure below the primary y=f(x) is the graph of function.
A graph of the function of the remodeling is the most suitable?

My tip to look at the remodeling of the graph is not known.
Given the graph f (x) = x +1, so

Do you know? Forty-two days 0 and 1 when the base falls below the curve, it's a right end!
Answer is4)