阅读下列短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

A

San Francisco Fire Engine Tours

San Francisco Winery Tour

   Running: February 1st through April 30th

   This delicious tour goes through the city on its way to Treasure Island where we will stop at the famous Winery SF. Here you can enjoy 4 pours of some of the best wine San Francisco has to offer.(Included in tickets price)

  Departing from the Cannery: Tell time upon request.

  Duration(时长)：2 hours

  Price: $90

Back to the Fifties Tour

  Running: August 16th through August 31st

  This tour transports you back in time to one of San Francisco’s most fantastic periods, the 1950s! Enjoy fun history as we take you through San Francisco for a free taste of ice cream.

  Departing form the Cannery 5:00 pm and 7:00 pm

  Duration:2 hours

  Price:$90

Spooky Halloween Tour

  Running: October 10th through October 31st

  Join us for a ride through the historical Presidio district .Authentic fire gear （服装）is provided for your warmth as our entertainers take you to some of the most thrilling parts of San Francisco

  Departing from the Cannery:6:30 pm and 8:30 pm

  Duration :1 hour and 30 minutes

  Price: Available upon request

Holiday Lights Tour

  Running: December 6th through December 23nd

  This tractive four takes you to some of San Francis’s most cheerful holiday scenes. Authentic fire gear is provided for your warmth as you get into the holiday spirit.

  Departing from the Cannery 7:00 pm and 9:00 pm

  Duration: I hour and 30 minutes

  Advance reservations required.

    I was a shy girl. I didn't even like to answer the telephone for fear I'd have to talk to somebody I didn't know. I enjoyed the loneliness of exploring nature. However, at school I had to spend all day in the company of others. My escape was reading. I spent a lot of time studying and was rewarded with good grades. My only failure was Spanish—I'd get all. As on my written work and tests, but Ds and Fs on the spoken part.

    Eventually I went to college. During my third year of college, I had enough of being shy and determined to change my outlook and behavior. One day while at school, I noticed an advertisement for positions on the local classical music radio station. I had grown up listening to classical music, and I could easily pronounce names such as Tchaikovsky, Albinoni, and Chopin.

    I had absolutely no background in radio, and absolutely no hope of getting the job. The idea of talking to thousands of listeners in “radio land” terrified me. However, I luckily survived the interview. I was given brief descriptions of symphonies（交响乐）and a public service announcement to read, and a list of composers' names to pronounce. It wasn't hard for me. I left the recording session（录音时段）with a sense of relief and a sense of accomplishment. About two weeks later I actually landed the job. It was a challenging job, but I grew to enjoy it greatly. I began to feel comfortable talking to people.

    Although I now spend many hours each week talking with people, I'm still basically a quiet person. Perhaps it is my soft voice and my quiet nature that helps draw people out as they respond to my questions as I interview them. My former shyness is a fortune, as I can relate to people who feel discomfortable when they talk to newspaper reporters. I still enjoy moments of loneliness and the peace found in nature. But I'm also glad I decided to make a change in my life that has opened many doors and opportunities that I never knew existed.

在极坐标系中，圆ρ=2被直线ρsinθ=1截得的弦长为（　　）

A、B、C、D、E五种物质为初中常见物质，反应关系如图所示（“﹣”表示相连的两物质能发生化学反应，“→”表示通过相应的化学反应可制得另一种物质，部分反应物、生成物略去）