If \( I(m, n) = \int_{0}^{1} x^{m-1} (1 - x)^{n-1} \, dx, \ m, n > 0 \), then \( I(9, 14) + I(10, 13) \) is:
\( I(1, 13) \)
\( I(9, 13) \)
\( I(19, 27) \)
\( I(9, 1) \)