e- This could be correct if we had a previous reference to it being the only one. If, say, I were looking for a specific book (linguistics) and found it, then this sentence would be OK. Without this, then 'linguistics; does not restrict it enough for the definite article.
f- With d), I would use either the indefinite or definite article depending on the degree of likelihood. Again, I would say that f) could work if we had some information about the likelihood.
Student or Learner