If $t_n = 1 + 2 + 3 + \dots + n$, then \[p_n = \frac{t_2}{t_2 - 1} \cdot \frac{t_3}{t_3 - 1} \cdot \frac{t_4}{t_4 - 1} \dotsm \frac{t_n}{t_n - 1}\]for $n = 2, 3, 4, \dots$, then $p_{1991}$ is closest to which of the following numbers?
(a) 2.0
(b) 2.3
(c) 2.6
(d) 2.9
(e) 3.2