Similarities:
They contain nematocyst (cells that sting)
some are sessil/free swimming
Some corals have a symbiotic relationship with algae, they need to grow in shallow waters so that light can penetrate for the algae to photosynthesize.
Answer:
A. single-gene
Explanation:
It is controlled by a single gene that has two alleles. The allele for a widow's peak is dominant over the allele for a hairline with no peak.
An apple is not an organism, but the cells within it are
