I am not sure whether this is a math problem. <may be is probability>

5 person A, B, C, D, and E each bought a lottery ticket. Only one of them strikes the lottery.

A said: C strikes the lottery
B said: A strikes the lottery
C said: A is lying
D said: I did not strike the lottery
E said: B strikes the lottery

Only one of them tells the truth. Who strikes the lottery?

A tells the truth

This is a logic problem,need to find contradiction,then find only one answer.

easy way is
U can see (A,C), ( B,D,E ) is contradiction for conditions(Only one of them strikes the lottery.Only one of them tells the truth)

so D strikes the lottery,C is telling the truth.

Oops , i made a mistake .

Or maybe we can try elimination .

If A strikes , then C and D are telling the truth
If B strikes , then C , D and E are telling the truth
If C strikes, Then A and D are telling the truth
If D strikes , Only C tells the truth
If E strikes, then C and D are telling the truth .

It says that only one tells the truth and only one strikes .
Thus D strikes a lottery and C is telling the truth .