EDMOND, Okla. -- North Dakota State is the pre-season choice to win its third straight national wrestling championship in 2001-02 according to the NCAA Division II Wrestling Coaches Association Top 20  poll.    The pre-season poll was determined using returning points from last year's national tournament.    The Bison of veteran head coach Bucky Maughn, who have captured three of the past four Division II national titles, return 65 points from last year's team that trimmed South Dakota State 98-91.5 for the championship.  Leading NDSU are two returning  individual champions -- 174-pounder Todd Fuller and heavyweight Nick Severson, who are both No. 1 in the individual pre-season rankings.    SDSU is second in the pre-season poll with 58  returning points and have three individuals ranked second at their respective  weights in 157 Aaron Veskrna, 165 Tyler Bryant and heavyweight Jon Madsen.    Central Oklahoma is third in the pre-season poll, with Nebraska-Omaha fourth and Ashland (Ohio) fifth.  Rounding out the top 10 is Pittsburgh-Johnstown (Pa.), Augustana (S.D.), Western  State (Colo.) and three teams tied for ninth -- Adams State (Colo.), Central Missouri State and Minnesota State-Mankato.    The team and individual rankings are in the rankings section on TheMat.com.