Select the number from among the given options that can replace the question mark (?) in the following series.
12, 25, 51, 103, 207, ?
$$12\times2+1 = 24+1 = 25$$
$$25\times2+1 = 50+1 = 51$$
$$51\times2+1 = 102+1 =Â 103$$
$$103\times2+1 = 206+1 = 207$$
$$207\times2+1 = 414+1 =Â 415$$
Hence '415' will come in place of the question mark.
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