What Makes the Metabolism of Ferroglobus Interesting in the Context

Multiple Choice

What makes the metabolism of Ferroglobus interesting in the context of evolution?

A) Ferroglobus is an anaerobic iron-oxidizing chemolithotrophic autotroph that may represent a key metabolism that allowed for the oxidation of ferrous iron without molecular oxygen.
B) Ferroglobus can use H₂ or H₂S as electron acceptors in its energy metabolism and is thermophilic, thus representing the earliest hypothesized forms of life.
C) Ferroglobus lacks cell walls and becomes encrusted in oxidized iron, suggesting that it may be an ancestor of other archaeans that lack cell walls.
D) Ferroglobus is both an iron- and nitrate-reducer and is probably the last common ancestor of all iron- and nitrate-reducing organisms.