Answer:
C. the use of hydrogen gas as an electron donor.
Explanation:
Hydrogenotrophy is the convertion of hydrogen gas to other compounds as part of its metabolism.
The pencil attached to the negative terminal of the battery collects hydrogen gas while the one connected to the positive terminal collects oxygen.
Do you have any pictures of your options
This problem is providing some chemical formulas and the number and types of atoms are required according to them; thus, we proceed as follows:
<h3>Chemical formulas:</h3><h3 />
In chemistry, we define chemical formulas as expressions showing the types and number of atoms a substance has. The types of atoms are found across the periodic table and the number is defined by the subscripts appearing in the formula.
a. It should be Fe₂O₃ as iron(III) oxide and in such a case it will have two iron atoms and three oxygen atoms.
b. It is potassium permanganate and it has one atom of both manganese and potassium and four oxygen atoms.
c. It should be CH₄, methane, and in such a case, it will have one carbon atom and four hydrogen atoms.
d. It should be NH₄NO₃, ammonium nitrate, and in such a case it will have two nitrogen atoms, four hydrogen atoms and three oxygen atoms.
Learn more about atoms and chemical formulas: brainly.com/question/5716048