选出可以填入空白处的最佳选项。 A teenager who once became homeless graduated at the top of his class in Houston, T

阅读下面短文，从短文后各题所给的A、B、C和D四个选项中，选出可以填入空白处的最佳选项。
 A teenager who once became homeless graduated at the top of his class in Houston, Texas this weekend. Derrick Ngo.18, had a   41   childhood, growing up without a father and finding his mother in and out of prison through the years.
Ahead of his   42   . Ngo had been to 12 different school, At 15, be started to   43   on his own with some help from his mother, but it was barely enough that he   44   homeless about two yean later. Ngo   45   his childhood to VOA. "We often didn't have that much food. We didn't have that much money. We didn't have a   46   source of income and that was one of my biggest   47   in growing up - that Lack of parental   48   ."
Determined to change his future, Ngo   49   all his frustrations (沮丧) into his studies-efforts that   50   landed him as the top student of his class at Energy Institute High School. "I   51   that if I didn't use schoold, education and the resources that were   52   to me, then there would be no way that I would get out of the   53   I was in," he said.
In December, Ngo learned that he had been   54   by Harvard, where he will be attending this fall. It was ,at frst, a    55   …I just got into Harvard. My heart was   56   ." he said. He was very excited. The young man   57   his success to discipline(自制力)and laser-like (激光一样的)   58   on end goals. "With a dream in your heart, you will have a clear   59   that you're working towards. Although it's not real yet, is   60   that is going to be real one day."
41. A. happy . B. boring C. troubled D. bright
42. A. failure B. difficulty C. independence D. achievement
43. A. live B. work C. learn D. train
44. A. got up B. grew up C. broke up D. ended up
45. A. recorded B. repeated C. recalled D. recommended
46. A. new B. stable C. spare D. balanced
47. A. desires B. features C. struggles D. advantage
48. A. pressure B. guidance C. training D. introduction
49. A. added B. counted C. combined D. directed
50. A. firstly B. slightly C. eventually D. unexpectedly
51. A. bet B. heard C. wondered D. remembered
52. A. donated B. available C. designed D. affordable
53. A. trap B. truth C. danger D. circle
54. A. told B. invited C. dismissed D. accepted
55. A. gift B. pity C. shock D. sympathy
56. A. rising B. racing C. beating D. sinking
57. A. owes B. devotes C. applies D. contributes
58. A. care B. focus C. confidence D. appreciation
59. A. goal B. way C. plan D. position
60. A. nothing B. anything C. everything D. something
【文章大意】这是一篇记叙文。作者讲述了自己成功的故事，他把成功归功于自律和对最终目标的专注。