Answer:
Difference of path length
Explanation:
When we look into glass of ice tea, from top to bottom path length will be more as compared to when we look from side of the glass.
According to Beer Lambert law, absorbance is proportional to the path length. Path length is the distance that light travels through the material.
More path length will lead to more absorbance of light and more the absorbance more the darker tea looks.
Moreover, tea is a homogeneous solution, therefore, concentration of will be same through out the solution. Since, concentration is same, therefore, the effect of gravity will be also be same on all particles.
Therefore, difference in path length is responsible .
So, the correct option is option a, difference in path length