What are the missing letters in these words? O

What are the missing letters in these words? O

[style]2[/style] [question] [{ 'title': 'What is the missing letter?', 'image':"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdG4RbRTvTvW6hKO-3odyRtneXQKABGMDYWhpkQH91kAaOXrIBDYBmmNBJzQeUqTEZAVtlzAdG-0BlFc6ao3_OpyUIQrXkcL7VyzQusCAMLayBXBT1GsC9hphsJ32mlz-5_M75ZbrdM1GpgraEnOq7HPZz2ygIvHEYMJlr8TfKLP44vWQAVky_9XjU/s600/1.jpg", 'answer': [ "__O", "A", "C", "B" ] }, { 'title': 'What is the missing letter?', 'image':"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF3GujM3j3rGLNGhQNvNZTQ7zuFVKYkTuQVEkQjR8SrG3OT_22jYHWQbbByKPSriHM4pdfa22L4uty6YF1_RC9PuvWr4uEfQ6C80lOenDYVJHLOm3MRXTwWHDthY0LJpi_fieDWNBHOBexs4gBHyEMGku5b_7RVSzDX8_Mhp7UplLQSoLCwxgvC0TC/s600/2.jpg", 'answer': [ "E", "__O", "R", "C" ] }, { 'title': 'What is the missing letter?', 'image':"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgbtkT4K2ZxtO5rw7Nb37hirEt3s6427VT4Ugdao0weKbj1jPjIfVo0DoI1DnzvcUaA1qu7KDgqZJLYdo3r0FVCJZ6hK1Ufp-1Ne18BxSaDqiGh0jlj9UQnlTezV9TXplpgnzdgCV6iycKMFkn_ALzF5SGi8tzxO4yYDG1fLr9AWlTNBWDUTF69LK_G/s600/3.jpg", 'answer': [ "E", "O", "__F", "B" ] }, { 'title': 'What is the missing letter?', 'image':"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgh0628dAHdQ1sdK4brFwi0Lbk_fQ_xZBhrCvPXzbSMTP5Hd2yEIRq4iQaGTl9lV_rnRyEfVGm6wl383NHKjOoHRx-u50HtQ6Lv0TOb4nTbsRB5igIn9PUN1Po6aYf0Mx0_tQ0QiuXOQdcjoCIVUQ606LnLNNdJOdtMLkvwi8jwXJpBwHGweXdjIgXM/s600/4.jpg", 'answer': [ "A", "O", "C", "__P" ] } ] [/question]