阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
Lightning flashed through the darkness over Sibson’s bedroom skylight（天窗）.Sibson was shaken by a clap of thunder ____21___ he knew what was happening. The storm had moved directly _____22____ his two-story wooden house. Then he heard the smoke alarm beeping.
Sibson rushed down the stairs barefoot to 23 ; he opened the door to the basement（地下室）, and flames 24 out. Sibson ran back upstairs to call 911 from his bedroom. “I felt 25 because the room had a separate outdoor stairway,” he explains.
But the phone didn’t work, and when he tried to go down the outdoor stairway, he was 26 by a wall of flames. Sibson realized he was trapped（困住）.
Sibson’s house was three kilometers 27 the main road and was so well hidden by trees that he knew calling for help would be 28 .
Up a hill nearby lived Sibson’s neighbor, Huggons. He was lying in bed when something like a smoke alarm 29 his ears. He jumped out of bed, took his 30 and flashlight, and headed down the hillside toward the 31 . That was when he saw the rolling heavy smoke.
Huggons dialed 911, and the operator warned him not to 32 the house. But Huggons said, “There is no way I am going to listen to Sibson 33 and die in that fire.”
“Anyone there?” Huggons called out. Then he heard “Help! I’m trapped!” coming from the second floor balcony（阳台）. He entered the house, but soon had to run back to catch his 34 .
