Trong các giới hạn sau giới hạn nào bằng −1?

\[\begin{array}{*{20}{l}}{\lim \frac{{2{n^2} - 3}}{{ - 2{n^3} - 4}} = \lim \frac{{\frac{2}{n} - \frac{3}{{{n^3}}}}}{{ - 2 - \frac{4}{{{n^3}}}}} = \frac{0}{{ - 2}} = 0.}\\{\lim \frac{{2{n^2} - 3}}{{ - 2{n^2} - 1}} = \lim \frac{{2 - \frac{3}{{{n^2}}}}}{{ - 2 - \frac{1}{{{n^2}}}}} = \frac{2}{{ - 2}} = - 1.}\\{\lim \frac{{2{n^2} - 3}}{{2{n^2} + 1}} = \lim \frac{{2 - \frac{3}{{{n^2}}}}}{{2 + \frac{1}{{{n^2}}}}} = \frac{2}{2} = 1.}\\{\lim \frac{{2{n^3} - 3}}{{2{n^2} - 1}} = \lim \frac{{2 - \frac{3}{{{n^3}}}}}{{\frac{2}{n} - \frac{1}{{{n^3}}}}} = + \infty .}\end{array}\]