A、It means being graded in biology. B、It means being able to break down naturally. C、It means being harmful to the environment.

W: Hello and welcome to today’s program. I’m Alice.
   M: And I’m Neil. Hello.
   W: Hello, Neil. Have you been shopping? Look at all those plastic bags. Why don’t you use your own bags?
   M: You know what, I’m going to, because they’re now charging 5p per bag!
   W: Don’t you follow the news, Neil? It’s a recent government initiative to cut the number of thin plastic bags being given away in shops. And the environmental impact of plastic is the subject of today’s show.
   M: Is England the first country to charge for these bags, Alice?
   W: No, other countries in the UK started charging a few years ago. And countries around the world including Bangladesh, South Africa, China, and Italy have actually banned them altogether.
   M: Interesting.
   W: So first, why do you think plastic bags are bad for the environment?
   M: Because they’re too thin? And when they break all your shopping falls out? That must be it.
   W: No. They take hundreds of years to decompose — or break down by natural chemical processes. And also people don’t dispose of them properly, They litter our streets. They spoil the countryside and damage wildlife.
   M: Well, that’s quite a list. So what’s the solution then, Alice?
   W: Well, to either recycle or stop using plastic bags. But a company in London is testing how bags made with a special additive break down when exposed to sunlight, oxygen and heat... The technology was discovered by a British scientist in the 1970s and is now sold to around half the world’s countries. In some, biodegradable bags are backed by law.
   M: And "biodegradable" means something able to break down naturally in a way that isn’t harmful to the environment.
   W: Yes. But if the technology was discovered back in the 1970s, why aren’t these biodegradable bags being used in every country by now?
   M: I have no idea. Maybe they aren’t as strong as non-biodegradable bags. I like a good strong bag, myself, you see.
   W: Alright. Well, just go and buy yourself some canvas bags. Now, moving on. Out of around 300 million tons of plastic produced every year, about 10% of plastic ends up in the sea. Some of these microplastics are actually being eaten by the zooplankton, those tiny little animals in the sea. We’re also concerned this could end up being passed up through the food chain to food which is destined for human consumption, so it could end up on your plate.
   M: What are microplastics, Alice?
   W: They’re small plastic fragments less than 5mm in size. You find them in cosmetic products such as facial scrubs, shower gel, and toothpaste. The zooplankton mistake the microplastics for food and eat them. And because the zooplankton and humans are in the same food chain — they’re at the bottom and we’re at the top - but we’re still connected — we may end up eating them and the microplastics inside them!
   M: That doesn’t sound very tasty!
   W: Indeed.
   This is the end of Conversation Two. Questions 6 to 10 are based on Conversation Two.
   Question 6
   Which country bans the use of plastic bags?
   (pause: 10 seconds)
   Question 7
   Why would plastic bags cause environmental pollution?
   (pause: 10 seconds)
   Question 8
   Why is the new plastic bag environmental-friendly?
   (pause: 10 seconds)
   Question 9
   What does "biodegradable" mean?
   (pause: 10 seconds)
   Question 10
   Where can microplastics be found?
   (pause: 10 seconds)