In which sentence does the verb agree with the subject?

a.
everyone in my class has taken the exam.

b.
someone in the neighborhood are mowing the lawn tonight.

c.
no one in the group know the answer.

Excerpt from jane eyre charlotte bronte 2 i was glad of it: i never liked long walks, especially on chilly afternoons: dreadful to me was the coming home in the raw twilight, with nipped fingers and toes, and a heart saddened by the chidings of bessie, the nurse, and humbled by the consciousness of my physical inferiority to eliza, john, and georgiana reed.