Answer:
The correct option is C) m∠POS = 20°, m∠POQ = 40°,
Explanation:
Consider the provided figure.
Meg constructed triangle POQ and then used a compass and straightedge to accurately construct line segment OS.
From the given figure it is clear that OS is angle bisector of POQ,

∴ angle bisector

Thus, the measure of ∠POQ is double the measure of ∠POS.
There is only one option in which m∠POQ is double the m∠POS.
Therefore, the correct option is C) m∠POS = 20°, m∠POQ = 40°,