bacteria, and fungi are some examples
Explanation:
The scientific notation:

where
and k is integer.
We have the example:

You can write the numbers in a "normal" form:

Make the sum:

And next write it in the scientific notation:

<h3>Other method:</h3>
You can add numbers in scientific notation if the power of tens in both number is the same.
Therefore you must convert the first number:

Now, you can make the sum:

I had this quiz too. The answer is carbon, hydrogen, oxygen. Hope this helps!
The Answer should be A. A consensus is defined as a general agreement so it is something most scientists would believe.