With no explanation, chose the best option from "A", "B", "C" or "D". against them. The Tiberts appeal. II [¶ 8] On appeal, the Tiberts argue the trial court erred in finding there was no justiciable controversy because the perpetual easement between Minto and Minto Grain rendered the Tiberts’ issue moot. The Tiberts contend the easement granted by Minto Grain to the City of Minto is not equivalent to an easement held in trust for the public for purposes of a public street. [¶ 9] When a trial court dismisses a case for mootness, we review the factual findings under the clearly erroneous standard set forth in Rule 52(a), North Dakota Rules of Civil Procedure. See Syversen v. Hess, 2003 ND 118, ¶ 9, 665 N.W.2d 23. However, a trial court’s legal conclusion of mootness is reviewed de novo. See Minnesota Humane Soc’y v. Clark, 184 F.3d 795, 797 (8th Cir.1999) (<HOLDING>); State v. Utvick, 2004 ND 36, ¶ 31, 675 N.W.2d

A: holding we review a dismissal for mootness de novo 
B: holding that we review constitutional challenges de novo
C: holding that we review a district courts interpretation of a statute de novo
D: holding that we review issues of statutory interpretation de novo
A.