English Translation
What killed Tom?
The sentence “Ne öldürdü Tom mu?” is not grammatically correct in Turkish.
Here are the correct alternatives depending on what you mean:
If you mean “What killed Tom?” → Tom’u ne öldürdü?
If you mean “What did Tom kill?” → Tom neyi öldürdü?
If you mean “Did Tom kill (someone/something)?” → Tom mu öldürdü?