We have built a supersymmetric SO(10) model consistent with cosmological
observations. The model gives rise to a false vacuum hybrid inflationary
scenario which solves the monopole problem. We argue that this type of
inflationary scenario is generic in supersymmetric SO(10) model, and arises
naturally from the theory. Neither any external field nor any external symmetry
has to be added. It can just be a consequence of the theory. In our specific
model, at the end of inflation, cosmic strings form. The properties of the
strings are presented. The cosmic background radiation anisotropies induced by
the inflationary perturbations and the cosmic strings are estimated. The model
produces a stable lightest superparticle and a very light left-handed neutrino
which may serve as the cold and hot dark matter. The properties of a mixed
cosmic string-inflationary large scale structure formation scenario are
discussed.Comment: 32 pages, uses RevTex. Misprint in a referenc