Answer: Inability to convert the light energy into chemical energy.
Step-by-step explanation:
The above question relates to the issue regarding photosynthesis. Plants contain chlorophyll and this helps them in the conversion of the light energy that they get from the sunlight into a chemical energy.
In the case that no yellow-leaved seedlings were found alive in either dish, the reason for this will mainly be because the plant was not able to convert the light energy into chemical energy.