Washington (CNN)GOP presidential candidate Ben Carson said Friday that he has better sources than the White House about the situation in Syria, sticking by his claim that China is involved in the fighting there. Carson previously said that the Chinese were involved in Syria in Tuesday's GOP debate, which the White House rejected. National Security Adviser Susan Rice said Thursday she has "not seen any evidence of Chinese military involvement in Syria" when asked about Carson's suggestions at a White House briefing. On Friday in South Carolina, Carson was pressed by CNN on whether he wanted to revise his earlier...