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A is corrent. This note was originally order paper because it was payable to the order of Ian Wolf. It next became bearer paper when Ian Wolf endorsed it on the back in blank, that is, without specifying any endorsee. When Samuel Thorn endorsed it and wrote "Pay: George Vernon," it became order paper. Next, when George Vernon endorsed it, it remained as order paper since he designated "Pay: Alan Yule." The last endorsement by Alan Yule was a blank endorsement which converted it to bearer paper.
B is incorrect. This note was originally order paper because it was payable to the order of Ian Wolf. It next became bearer paper when Ian Wolf endorsed it on the back in blank, that is, without specifying any endorsee.  
C is incorrect.   This note was originally order paper because it was payable to the order of Ian Wolf.
D is incorrect. This note was originally order paper because it was payable to the order of Ian Wolf. It next became bearer paper when Ian Wolf endorsed it on the back in blank, that is, without specifying any endorsee.