Which preposition to use with extenuation

of Occurrences 51%

He began with quiet remonstrance, and ended with an unheard extenuation of his presumption.

for Occurrences 3%

Bad as the gambling business was and deeply as he regretted the expulsion from college the doctor could not help seeing that there was some extenuation for Ted's conduct, that he had in the main kept faith with himself, paid generously, far more than he owed, and traveling through the fiery furnace had somehow managed to come out unscathed, his soul intact.

from Occurrences 1%

They were clad in silken extenuations from the throat to the feet, and wore, withal, a pathos in their charm that gave them a family likeness to innocence.

with Occurrences 1%

Mrs. Sinclair and the nymphs are all of opinion, that I am now so much a favourite, and have such a visible share in her confidence, and even in her affections, that I may do what I will, and plead for excuse violence of passion; which, they will have it, makes violence of action pardonable with their sex; as well as allowed extenuation with the unconcerned of both sexes; and they all offer their helping hands.

Which preposition to use with  extenuation