The most common cause is depression.
I hope this hellps you.
1. Domain > Kingdom > Phylum > Class > Order > Family > Genus > Species
2. Two parts; the the generic:genus name and the species name/specific epithet
3. six
4. they both belong to the archaea domain
5. they both belong to the archaea domain & the animalia kingdom
The answer is D; eliminate snack foods and chocolate