Noun: desafio
Verb: contestar, desafiar, impugnar, questionar, embargar
(verb) to object to; to question the legality of something or the legal qualifications of someone.
"The defendant challenged the qualifications of the expert witness."
Synonym: object: "The plaintiff objected to the witness' testimony on the grounds that it was hearsay."
challenge (noun) - objection or question. "The international treaty was not open to challenge in the Supreme Court."
legal challenge - an adversarial proceeding. "The statute was subject to a legal challenge in the district court."
to challenge the law - to bring legal action to have a law repealed. "The Association of Nurses challenged the law which required them to report the immigration status of patients."
ação contestada = the action was challenged
valor questionado = the amount was challenged