If it was "a bat eats a bee" it would include the word "mot". But because it doesn't, it would be "the bat eats the bee". Also, I think if the sentence includes the classifiers (in this case "con") then it automatically means it's "the". I might be wrong about that last bit though.
The "ng" sound is swallowed. The mouth closes at the end, which makes it sound a bit like an "m" sound.