Four people, A, B, C and D, are suspects in a murder case, where exactly one of them is the murderer. The victim has been murdered by a knife during a stormy night at her residence in a small town. All four of the suspects made two statements each. It is known that for each of them, one statement is correct and one statement is wrong, although, at the outset, it is not known which one is correct and which one is wrong. 
A:  I.  I have never touched a knife in my life.   II.  I was not in town on the night of the murder. 
B:   I.  A is the murderer.   II.  I was playing cards with C the entire night of the murder. 
C:  I.  I was sleeping on the night of the murder.   II.  B is innocent. 
D:  I.  C is innocent.   II.  B is the murderer.