What would be a benefit of using metagenome sequencing of viral dsDNA genomes isolated from a seawater sample?

a. ORFs can be identified from the metagenomic sequence data
b. This would be the only way to obtain a viral genome
c. Viral genomes are small, so this would be a fast way to sequence them
d. All dsDNA viruses present in the sample are sequenced, rather than having to identify hosts to propagate the viruses