Please submit your concern

Explanation:

The given statement “The relations between probability and experience are still in need of clarification” hints that while probability and experience are linked, their precise relationship requires further elucidation.
Option 1 can be eliminated because of the word “always” which indicates a precise relationship between experience and probability.
Option 2 can be eliminated due to similar reasons, as it indicates that probability is entirely dependent on history.
Option 3 distinguishes probability from experience by calling one “real” and the other “mathematical”; no such comparison has been made in the passage.
Option 5 can be eliminated since the implications of the future on probability are not suggested in the passage.
Option 4 alone holds since it does not dispute the link between “probability” and “experience” and is vindicated from the lines - “The second task is to elucidate the relations between … decidability of probability statements”.
Hence, the correct answer is option 4.