Is Dai's failure to provide corroborative evidence sufficient to establish that she is not credible?

Having found Dai not credible, the agency reasonably noted that her failure to provide corroborative evidence further undermined her credibility. An applicant's failure to corroborate her testimony may bear on credibility, either because the absence of particular corroborating evidence is viewed as suspicious, or because the absence of corroboration in general makes an applicant unable to rehabilitate testimony that has already been called into question. See Biao Yang v. Gonzales, 496 F.3d 268, 273 (2d Cir. 2007).