Hey there!
Here is the answer to your question.
Answer : <em>A - b</em>
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<em>The reason why is you have refraction and reflection. Meaning, that you arrow B is being reflected. </em>
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<em>I have included the vocabulary definitions I have studied for you and how I got the answer. </em>
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<em>Refraction - </em><em>It is the activity of bending the light. When the light that going from rarer medium to denser medium, the light soon bends towards its normal line.</em>
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<em>Reflection - </em><em>When the light ray is falling on the surface, then the ray that is coming from outside of the surface is known as a reflected ray. </em>
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<em>In your reflection, the incident angle is now equal to the best reflected angle!</em>
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<em>I hope this helps you!! ☺</em>
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