Which number line shows the solution to −3 − (−1)?

a number line is shown from negative 5 to 0 to positive 5. there are increments of 1 on either side of the number line. all the numbers are labeled on either side of the number line. an arrow pointing from 0 to negative 3 is shown. above this, another arrow pointing from negative 3 to negative 4 is shown. a vertical bar is shown at the tip of the arrowhead of the top arrow.
a number line is shown from negative 5 to 0 to positive 5. there are increments of 1 on either side of the number line. all the numbers are labeled on either side of the number line. an arrow pointing from 0 to 3 is shown. above this, another arrow pointing from 3 to 4 is shown. a vertical bar is shown at the tip of the arrowhead of the top arrow.
a number line is shown from negative 5 to 0 to positive 5. there are increments of 1 on either side of the number line. all the numbers are labeled on either side of the number line. an arrow pointing from 0 to negative 3 is shown. above this, another arrow pointing from negative 3 to negative 2 is shown. a vertical bar is shown at the tip of the arrowhead of the top arrow.
a number line is shown from negative 5 to 0 to positive 5. there are increments of 1 on either side of the number line. all the numbers are labeled on either side of the number line. an arrow pointing from 0 to 3 is shown. above this, another arrow pointing from 3 to 2 is shown. a vertical bar is shown at the tip of the arrowhead of the top arrow.