evenly-distributed soft CCCP sources is a factor of 2 higher than our Galactic contamination prediction (§\[qualitative\_analysis\_section\]). This discrepancy may be due either to unmodeled effects (e.g., stars beyond $D = 5$ kpc, an additional population of MS stars in the Carina spiral arm, or evolution of X-ray activity in older stars), or the presence of a widely distributed population of young stars in the Carina complex. The inference of distributed star formation, or the kinematic drifting of an older generation of Carina stars, is substantiated by more detailed studies of the CCCP sources lying outside the rich clusters [@Feigelson11; @Preibisch11; @Povich11b].

We thank the anonymous referee for his time and many useful comments that improved this work. This work is supported by $Chandra$ GO grant SAO GO8-9131X (L. Townsley, PI) and the $Chandra$ ACIS Team contract SV4-74018 (G. Garmire, PI), issued by the Chandra X-ray Center operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA under contract NAS8-03060. M.S.P. is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-0901646. This publication makes use of data products from the Two Micron All Sky Survey (a joint project of the University of Massachusetts and the Infrared 