Option D is correct.
<h2>Piecewise function</h2>
is a function that is defined on a sequence of intervals and built from the piece of different functions. It is one that is defined not by a single equation, but by the two or more each equation is valid for some interval.
Given
f(x) = x +1, is a function.
<h3>To find </h3>
The domain for the piece of the function.
<h3>How to get the domain for the piece of the function?</h3>
From the graph, we can clearly see that at x = 1, there is a jump of 1 unit in y. hence it is divided into two parts.
For x > 1 the domain is defined up to ∞.
For x ≤ 1 the domain is defined up to -∞.
Thus the option D is correct.
More about the piecewise function link is given below.
brainly.com/question/17966003