请阅读下面两篇短文，掌握大意，然后从下列各各题所给的四个选项（A、B、C、D）中，选出最佳选项，并在答题卡上将该选项的标号涂黑。

When Joe was about to start school. all signs pointed to success. Yet things turned out to be quite 36 .The fourth grade even found him at the 37 of the class. Joe struggled day and night, but it did not 38 -until one stormy aftermoon .

On that aftermoon ,39 the math teacher started to introduce difficult concepts, dadk Clouds covered the sky, and the stone ad in. Hard thou she tried to make the kids，40 ,the thunder won the battle for their attention .No one 41 the concepts. Except Joe. He undemtood them and answered all the questions correctly. The teacher patted him on the back. and told him to go around to the others and explain how he had managed it. 42 by his newfound success. Joe moved quickly throughout the room. Soon math time was followed by the time for 43 .All children naturally drew 44 pictures on such a day. Except for Joe.

Since then, Joe started 45 . Though he never made it to the top, his math teacher was always 46 and curious about the change: Why had that stomry day changed Joe?

On the day Joe graduared, he presented the teacher with his moat 47 possession—the picture of.bright yellow sun .On the picture Joe had written: This is the day I 48 my brightness.