Final answer:
The boy observed germination in pots 'A' and 'C'. Pot 'A' was covered with an opaque glass, while pot 'C' was covered with clear plastic.
Step-by-step explanation:
The boy observed germination in pots 'A' and 'C' after 4-5 days. Pot 'A' was covered with an opaque glass, which excluded all light and allowed the seeds to germinate. Pot 'C' was covered with clear plastic, which allowed light to reach the seeds, resulting in germination as well. Pot 'B' was covered with frosted glass, which diffused the light and may have affected the germination process.