madham - as the first two answers have already stated, the correct answer is that Ned ate it. There is not need for you to stay in suspense, because we have already worked it out. In order to work out the correct answer, all you have to do is
1. assume Linda ate it, and work out how many of the statements are true and false;
2. assume Mike ate it, and work out how many of the statements are true and false;
3. assume Ned ate it, and work out how many of the statements are true and false;
4. assume Olive ate it, and work out how many of the statements are true and false.
The assumption that Ned ate it is the only one which leads to 1 true statement and 3 false statements, so that must be the correct one. (The other three assumptions all lead to more than one true statement, so they contradict the information given in the question).