Which sentence from the article above features improper parallelism?

A. "Few American writers have had as much influence on the literary canon
as Emily Dickinson."

B. "These pieces were collected and edited by Thomas Higginson, a former
mentor of Dickinson's."

C. "Though she had a brief stay at Mount Holyoke Seminary and a stay in
Boston for eye treatment, she almost never left her home."

D. "Dickinson's poems tended to be short, she punctuates them with dashes,
and featured quirky innovations pf word order."