With no explanation, chose the best option from "A", "B", "C" or "D". legal conclusions is de novo, but we defer to the BIA’s reasonable interpretations of the INA. Patel, 432 F.3d at 692 (citing INS v. Aguirre-Aguirre, 526 U.S. 415, 424-25, 119 S.Ct. 1439, 143 L.Ed.2d 590 (1999)). What the petitioner is seeking in this appeal is for the adjustment of his status as though he had never departed from the United States after his initial entry. He claims that the BIA erred in determining it had no authority to grant his application for adjustment of status nunc pro tunc. Petitioner asserts that he is entitled to nunc pro tunc relief because (1) agency error in the form of a misplaced file meant he could not timely secure a joint motion to reopen removal proceedings, and (2) the 2008 case of Dada v. Mukasey, 554 U.S. 1, 128 S.Ct. 2307, 171 L.Ed.2d 178 (2008) (<HOLDING>) demonstrates that it was the Agency’s

A: holding the respondent  implicitly exercised his right to withdraw his voluntary departure request and instead  elected to remain to pursue his motion
B: holding that bia did not err in denying motion to reopen that was filed after expiration of aliens voluntary departure period because alien had failed to depart
C: holding that aliens must be permitted to unilaterally withdraw voluntary departure requests in order to pursue motions to reopen
D: holding the bia did not err in denying aliens motion to stay voluntary departure period pending determination on the motion to reopen
C.