Answer:
<u>A. Red Algae</u>
Explanation:
I'm not entirely sure if it's red algae, but it's most likely to be the right answer.
<u>Hope this helps!</u>
The mass number is the sum of the number of protons and number of neutrons the atom has.
So, we can write the equation as:
x + 20 = 40
x = 20 neutrons.
Nucleus is the correct choice, bacteria cells lack a Nucleus
