Read the passage and circle the letter A, B, C, or D to indicate the best option for each of the questions.

Red Claw Crawfish

Red claw crawfish (also known as crayfish), an invasive species but a favored dish in some provinces in Vietnam, is a threat to the country's agriculture and fisheries. Native to northern Australia, crawfish has entered Vietnam mainly frozen from the US or fresh (imported illegally from China). This kind of crawfish was first imported for food a few years ago and quickly became popular. However, lots of scientists believe that the species could become a disaster for both agriculture and the ecosystem. The crawfish withstand environmental changes, so they are strong and reproduce quickly. They feed on almost all kinds of aquatic species and compete with local shrimp species for food. If they live with other native species in the same environment, it is possible that some local fish or shrimp species could disappear. Moreover, with their strong claws, they easily cut rice paddy stalks, eat young buds as well as dig in and destroy dykes. They could also spread diseases and viruses that could damage the crops.

Measures have been taken to protect the biodiversity and avoid bad impacts of crawfish on agricultural production. In 2013, Vietnam put crawfish on the list of foreign species that are banned from being imported. Then in 2018, all activities related to raising and distributing the creature are prohibited. People have to pay a fine of 100 million VND to 1 billion VND or even go to prison up to five years for importing and distributing this invasive species. However, controlling the trade in crawfish has been a difficult task, because it is usually smuggled into Vietnam in small quantities via minor border gates, such as in Lang Son or Lao Cai Province and is sold mainly by merchants via social networks.

Read the passage and circle the letter A, B, C, or D to indicate the best option for each of the que...