What does the words "effluence of their very core" mean?

Read the following passage carefully and choose the most appropriate answer to the question out of the four alternatives.

Great books do not spring from something accidental in the great men who write them. They are the effluence of their very core, the expression of the life itself of the authors. And literature cannot be said to have served its true purpose until it has been translated into the actual life of him who reads. It is the vast reservoir of true ideas and emotions. In a world deprived of literature, the broad, the noble, the generous would tend to disappear and life would be correspondingly degraded, because the wrong idea and the petty emotion would never feel the upward pull of the ideas and emotions of genius. Only by conceiving a society without literature can it be clearly realised that the function of literature is to raise the plain towards the top level of the peaks. Literature exist so that where a man has lived finely, ten thousands may afterwards live finely. it is a means of life, it concerns the living essence.