<span>300BC was the approximate year.
</span>
I would say C. Reduce climate change because taking a car/vehicle results in the earth becoming polluted which leads to climate change.
*EXPLANATION*
Riding your bike or walking will not do anything to help people chopping down trees, people giving birth to more and more children nor will increase the amount of animals/organisms we have on our planet.
I think the answer is organisms
Tadpoles use GILLS to obtain oxygen
By studying the fossil record we can tell how long life has existed on Earth, and how different plants and animals are related to each other. Often we can work out how and where they lived, and use this information to find out about ancient environments.
