The fact of the matter is that most religious scholars believe the fruit was (if you believe in the mythology of Christianity) a pomegranate or the fig. Apples are not indigenous to the middle east, or the surrounding areas, and therefore the fruit or the trees would not have existed ~6,000 years ago. Thus, it would be an impossibility that said fruit would have existed at that time and place.
Furthermore (if you want to say: "Well, God just put it there ala deus ex machina!"), the book of Genesis NEVER SAYS "APPLE". It simply says "fruit". Early rabbis and scholars debated on what "fruit" this was and came up with things including grapes, citron, wheat, the carob, and of course the pomegranate and fig.
So where did this "apple" come from? Given that it's not mentioned in the story of Adam and Eve, thats a good and convoluted question. Most modern day scholars believe that Christians adopted the apple due to the apple's Latin name "malum" which also happens to mean "evil". In fact the apple didn't even start showing up in Christian iconography or texts until the mid 16th century and only then in Europe (where the apple actually grows naturally unlike the middle east).
So, no. It was not the apple. If you want to get technical the Bible never really says WHAT it is. Only that it was a "fruit", so one would assume that the actual fruit isnt important, but rather the moral of the story is.
This is just another example of how the Christian machine has gotten out of hand and has strayed from the actual beneficial teachings surrounding it's theology.