Choose the sentence that best combines each pair of sentences given.

Fossil fuels come from dead plants and animals. These plants and animals died millions of years ago.

Deforestation and loss of habitat threaten many species so that they will become extinct.

Many species lost their habitat because of deforestation and now they are extinct.

Deforestation and loss of habitat are driving many species to the verge of extinction.

Many species are extinct, so they run the risk of deforestation and loss of habitat.

We can no longer remember having advised you on how to decrease your energy use.

We remember having advised you on how to maintain your energy use.

We remember having advised you on how to decrease your energy use.

We remember to have advised you on how to decrease your energy use.

Because of releasing a large amount of carbon dioxide, motor vehicles run on petrol.

A large amount of carbon dioxide emission results from motor vehicles running on petrol.

A large amount of carbon dioxide emission causes motor vehicles to run on petrol.

Emitting a large amount of carbon dioxide is one of the responsibilities of motor vehicles running on petrol.

The environment has been made catastrophic by global warming.

It is true that global warming is a catastrophe caused by the environment.

It has been proven that global warming is harmful to the environment.

The environment has been truly dangerous because of global warming.

It is alarming that deforestation damages the quality of the land.

The quality of the land deteriorates as the result of the alarming rate of deforestation.

The alarming rate of deforestation results from damage to the quality of the land.

The damage to the quality of the land is to blame for the alarming rate of deforestation.

Some animals go extinct due to changes in climate where they live.

Climate changes make some animals go extinct where they live.

The climate changes where some animals there go extinct.

That some animals go extinct causes the climate where they live to change.

Some scientists were accused of having falsify the effects of climate change.

Some scientists were accused of having been honest about the effects of climate change.

Although some scientists have distorted the effects of climate change, they were not accused.

Some scientists were accused of having falsified the effects of climate change.