Under what circumstances must a defendant be found to have violated his probation?

(People v. Rodriguez (1990) 51 Cal.3d 437, 441) and the evidence must only show the violation was willful. (People v. Galvan (2007) 155 Cal.App.4th 978, 981-982.)

" 'In reviewing a challenge to the sufficiency of the evidence [to support a finding that a defendant violated his probation], we do not determine the facts ourselves. Rather, we "examine the whole record in the light most favorable to the judgment to determine whether it discloses substantial evidenceevidence that is reasonable, credible and of solid valuesuch that a reasonable trier of fact could find [by a preponderance of the evidence that] the defendant [violated probation.]" [Citations.] We presume in support of the judgment the existence of every fact the trier could reasonably deduce from the evidence. [Citation.] ... We do not reweigh evidence or reevaluate a witness's credibility.' [Citations.] 'Resolution of conflicts and inconsistencies in the testimony is the exclusive province of the trier of fact. [Citation.] Moreover, unless the testimony is physically impossible or inherently improbable, testimony of a single witness is sufficient to support a [finding that the defendant violated probation].' " (People v. Brown (2014) 59 Cal.4th 86, 105-106.)