Which case type can function as a subject or predicate nominative only

Plz asap read this sentence from paragraph 3 of the article. the boys and girls are merely asked to obtain the signatures of ten friends or relatives. how does the word "merely" affect the meaning of the sentence? a- it suggests that asking people to subscribe to the washington times is something negative. b- it implies that obtaining ten signatures is not a requirement for receiving a prize. c- it downplays the fact that to win the prize, children must ask people to subscribe to the washington times. d- it emphasizes that children receive the prize only if they obtain ten signatures.