An elderly woman has had difficulty with digesting her foods because of reduced stomach acid, has had progressively worse nerve pain in her legs, and is now having difficulty walking. her physician suspects she may have a deficiency of which vitamin?

option number one would be youre best option

many phylogenetic trees have a single lineage at the base representing a common ancestor. a lineage that evolved early from the root and remains unbranched is called basal taxon. when two lineages stem from the same branch point, they are called sister taxa.

can i get the brainliest pls

explanation: