Your answer is actually all correct. Great job! A heterozygous combination would just implicate greater power to the 'dominant' dominant allele.
The answer is D, algae.
—Evidence—
•] Protozoan definition: a single-celled microscopic animal of a group of phyla of the kingdom Protista, such as an amoeba, flagellate, ciliate, or sporozoan.
•] it does not feature algae, therefore it’s D.
Answer:
Prevent the cell from collapsing
Explanation:
Not 100% positive