1681,41,1764,42,1849,43,_
D
Correct answer
Explanation
This is a number sequence pattern. The sequence alternates between perfect squares: 1681 (41^2), 1764 (42^2), 1849 (43^2), and then 1936 (44^2). The pattern is: square(n), n, square(n+1), n+1, square(n+2), n+2, square(n+3). Following this pattern, after 43 comes 1936 which is 44^2.