Chinese son preference is on the downward trend, actually but if you insist, let's start again with dowry payments:
Siwan Anderson, The Economics of Dowry and Brideprice, The Journal of Economic Perspectives, Vol. 21, No. 4 (Fall, 2007), pp. 151-174
www.jstor.org
Care for the elderly:
Preference for sons over daughters, evident in China's and South Asia's male sex ratios, is commonly rationalized by poverty and the need for old-age su...
www.jstor.org
Son preference isn't influenced by "misogyny". If anything, there's a shitload of expectations on sons in South-East Asia, about "continuing the bloodline" and care for the elderly members of the family, which skews the sex ratio further, which exacerbates the problem.
China only in 2009 implemented a pension scheme for old age in rural areas, where, surprise, most of the female foeticide happens:
The sustainable development of pension systems has been investigated from a financial perspective worldwide. However, the pension adequacy and its effect on the sustainability of a national pension system are still understudied. Using actual replacement rate and modified living standards...
doi.org
It's a pragmatic choice within the South-Asian culture and not China specifically. Regardless of industrialization, the dowry system continues and so the expectations upon males to provide.