Guangdong is known for its famous agricultural products. Here are some of the most famous and well-known products:

1. Pearl River shrimp
2. Crayfish
3. Sea cucumber
4. Grass carp
5. Black-necked clam
6. Oyster
7. Pork
8. Chicken
9. Duck
10. Shrimp

Which of these products is considered the most famous and well-known?