DETROIT (Reuters) - California, the largest U.S. car market, plans to allow testing on public roads of self-driving vehicles without human backup drivers by the end of the year, state officials said Friday.<div><a href="http://feeds.reuters.com/~ff/reuters/technologyNews?a=oZdvFrGskO0:tjzg5gtEERQ:yIl2AUoC8zA"><img src="http://feeds.feedburner.com/~ff/reuters/technologyNews?d=yIl2AUoC8zA" border="0" /></a> <a href="http://feeds.reuters.com/~ff/reuters/technologyNews?a=oZdvFrGskO0:tjzg5gtEERQ:V_sGLiPBpWU"><img src="http://feeds.feedburner.com/~ff/reuters/technologyNews?i=oZdvFrGskO0:tjzg5gtEERQ:V_sGLiPBpWU" border="0" /></a> <a href="http://feeds.reuters.com/~ff/reuters/technologyNews?a=oZdvFrGskO0:tjzg5gtEERQ:-BTjWOF_DHI"><img src="http://feeds.feedburner.com/~ff/reuters/technologyNews?i=oZdvFrGskO0:tjzg5gtEERQ:-BTjWOF_DHI" border="0" /></a></div><img src="http://feeds.feedburner.com/~r/reuters/technologyNews/~4/oZdvFrGskO0" height="1" width="1" alt="" />