  We discuss a chemical evolution model with Z-dependent yields that reproduces
the O/H, C/H, and C/O gradients of the Galactic disk and the chemical history
of the solar vicinity. The model fits the H, He, C, and O abundances derived
from recombination lines of the HII region M17 (including the fraction of C and
O atoms embedded in dust); the protosolar H, He, C, O, and Fe abundances; and
the C/O-O/H, C/Fe-Fe/H, and O/Fe-Fe/H relations derived from stars of the solar
vicinity. The agreement of the model with the protosolar abundances at the
Sun-formation time implies that the Sun originated from a well mixed ISM at a
galactocentric distance of 7.6 $\pm$ 0.8 kpc.
