Answer:
C) 1.32 units
Explanation:
The vertical line extends from y = -0.36 to y = 0.96. Its length is ...
0.96 -(-0.36) = 0.96 +0.36 = 1.32 . . . units
The length of the red line segment is 1.32 units.
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Additional comment
When reading a graph, it is always a good idea to understand what the vertical and horizontal scales are. In the real world, not only are they commonly different, but they can also be (intentionally) misleading.