What is an organism that breaks down and gains nutrients from dead organisms?

Q: a pair of homologous chromosomesa) always has the same genes and the same allows b)always has the same genes c)always has the same alleles d)never has the same genes

All vaccination should(n’t) be mandatory! 1.at least 5 sentences explaining 2.why? 3.in the end summarize the sentence

Which would be the most useful source of evidence to support mcneill's contention?