The most important cause of loss of biodiversity today is:

1. habitat loss and fragmentation

2. over-exploitation

3. alien species invasions

4. co-extinctions

Loss of biodiversity may lead to all except:
1. decline in plant production
2. increased resistance to environmental perturbance
3. increased variability in water use
4. increased variability in pest and disease cycle

Biodiversity loss is now one of the world's most pressing crises. The primary reason for this is:
1. we cannot do anything about it
2. we are not responsible for this loss
3. we still do not know its entire extent
4. it is affecting only the developing countries

The main difference between "Sixth Extinction" and the previous five extinctions is that the sixth extinction:
1. is mainly occurring on islands
2. is mainly affecting plants
3. is occurring at a faster rate
4. does not involve human activities

What is applicable to both Lates niloticus and Lantana camara ?

1. They are on the verge of extinction due to over-exploitation by humans.

2. They are alien species that became invasive in certain environments causing threat to indigenous biodiversity.

3. They are mutualists and likely to undergo co-extinction in recent future.

4. They are keystone species and are vital to the stability of tropical ecosystems.