The correct answer is - C. Volcanic derived carbon dioxide gas bubbled from the lake and suffocated people and animals nearby.
In the summer of 1986, more specifically on the August 21st, a big tragedy happened in Cameroon. The Lake Nyos, located in the northwestern part of the country experienced a limnic eruption. This eruption triggered the release of very large amounts of carbon dioxide from the lake. The exact amount of carbon dioxide that was released is debatable, and the general consensus is that it was between 100,000 and 300,000 tons of the gas, though there are suggestions that it was up to 1.6 million tons.
The gas spread around very quickly, and being heavier than the air it stuck very low. In a radius of around 25 km from the lake, lot of people and animals were suffocated. The estimates are that 1746 people died and around 3,500 livestock died, not even counting the damage that has been done to the wild animals.
The creation of approximately ten million refugees from 1947-48 was a result of World War II.
World War II brought destruction of lot of countries, millions of people lost their homes that were flattened with the ground, the economies were destroyed and on the verge of bankruptcy, so millions of people left their countries in search for better life (or rather just normal life).
Let's start from the beginning.
<span>Millions and millions of years ago, planet Earth was absolutely crowded with volcanoes. </span>
<span>As you may know, volcanoes release steam and gasses. </span>
<span>As the years went by, the gasses released from volcanoes formed the atmosphere around the planet, which prevented the steam from disappearing into outer space. </span>
<span>The steam eventually, in cycles, began to fall back to Earth. Viola, rain had just been "invented". </span>
<span>As more and more rain fell, considering almost every surface of the planet was volcanic, the water began to build up and "flood" the planet. Many active volcanoes had now been transformed into underwater volcanoes. </span>
<span>As more and more years went by, eventually, bacteria in the water slowly began to evolve, first into jelly-fish like creatures, then tadpole-like creatures, leading all the way up to large ferocious underwater reptiles, amphibians and fish. </span>
<span>As the planet started to warm up, probably by methane gasses released from the prehistoric underwater creatures, the water levels on Earth began to drop again. At the same time, the active underwater volcanoes were creating new landmasses, either by lava cooling on the surface of the water or tectonic plates pushing the volcano above sea level. </span>
<span>So, this, is how fossils of sea creatures ended up in high land-based mountains. </span>
<span>Because millions of years ago, most of Earth was underwater until the water levels dropped or lands "grew" higher. </span>
<span>The Rocky Mountains were once underwater. </span>
<span>If you take a look at images of the Grand Canyon in the United States, you'll see that it resembles the deep caverns and canyons that you find at the bottom of oceans. </span>
<span>That's because the Grand Canyon WAS at the bottom of an ocean.</span>
Answer:
<em>Thermosphere</em>
Explanation:
<em>The </em>thermosphere<em> is one of the different layer of the atmosphere from all the other layers of atmosphere.</em>
<em>As thermosphere does not consist of mix gases, and it only consist of one gas. It is on the up of mesosphere and it remains down of the exosphere. And ultraviolet radiation are also caused in this particular layer of the amosphere of the earth.</em>
