Answer:
b. the presence of chloroplasts
Explanation:
The presence of chloroplast is a character being common to all the groups of green algae (to which charophytes belong) but also to plants, if one associates "plants" to the group formed by non vascular plants (mosses and relatives), non seeded vascular plants (ferns and lycophytes) and seeded plants (conifers or gymnosperms and flowering plants or angiosperms).
Thus, as the presence of chloroplasts is common throughout all these groups, it does not provide any taxonomic relevant information to particular link the charophytes to the land plants (or embryophytes, all the taxa above mentioned) as their closest relatives.
