I guess the answer is most likely b) they are rare.
solar eclipses can occur fairly often, sometimes 2-4 times a year
That would be C. Uracil.
In RNA we’ve got Uracil instead of Thymine.(which is in DNA)
I'd go with the third one because the products of both of them are oxygen and carbon dioxide.
The answer is C. Aromatase
Metamorphic rocks can be formed by <span>all three types of rocks, igneous, sedimentary, and metamorphic</span>
