C. The street got its name due to the original architecture there.

D. The English adopted the name in memory of the original wall.

2. Among the important landmarks, which used to stage certain political events?

A. Trinity Church. B. Federal Hall National Memorial.

C. The New York Stock Exchange. D. Bankers Trust Company Building.

　　B

　　Do you like cholocate? It's popular all over the world, but why? Scientists have been trying to discover its secrets.

　　The main thing is that chocolate makes us happy. This may have something to do with the 380 known chemicals found in it. The problem is that many of these chemicals appear in other types of food too. So, it's difficult to know why the ones in chocolate make us feel good. But we aren't all lost. Adam Drewnowski at the University of Michigan found that chocolate makes the human brain produce natural opiates, called opioids(鸦片). These can stop pain and make us feel good.

　　Others think that we feel good after eating chocolate because of a chemical called anandamide. This occurs naturally in the brain and seems to give us a feeling of happiness. Normally, our levels of anandamide are very low and our body uses it quickly. But two scientists, Emmanuelle di Tomaso of Harvard University and Daniele Piomelli of the University of California believe that the anandamide in chcocolate raises levels of the chemical in our brain. And other substances in chocolate slow down the speed at which we use it. So, chocolate helps us feel happier for longer! Great!

　　But which chocolate is the best? Well, for a start, there's more anandamide in dark chocolate than milk chocolate. So, you need to buy some dark chocolate. Then, you should follow these five tips from connoisseur chocolate makers Ghirardelli. They say that when choosing chocolate, you need to use all five senses:

　　1.Sight: good chocolate has a shine to it.

　　2.Smell: rub the chocolate with your finger to release the aroma. It should have a deep chocolate smell.

3.Sound: when you break a piece of chocolate it should snap crisply, creating a sound similar to that of a thin piece of wood being broken.