The 18th National Congress of the Communist Party of China was held at 9: 00 a.m. on October 8, 20 12/KLOC-0, and the closing meeting was held at 9: 00 a.m. on October 8/KLOC-0.

B is between vernal equinox and summer solstice, C is between summer solstice and autumn equinox, D is between autumn equinox and winter solstice, and A is between winter solstice and vernal equinox. The 18th National Congress of the Communist Party of China was held at 9: 00 a.m. Beijing time at 2012+01. Section d of the four sections.

Therefore, choose: d.