In which sentence does the underlined gerund function as the object of a preposition

Proofread this excerpt from a review of the film tangled. what type of errors does it contain? walt disney studios is back with another delightful film sure to entertain children and adults alike, hat’s off to the writer and director of this charming little endeavor. they have effectively managed to breathe new life into an old classic: by giving rapunzel's tale a fresh twist, instead of the meek and rapunzel of the original disney story; this retelling gives us a spunky and assertive heroine ready to take command of her own life. a. mixed-up tenses b. incorrect verb usage c. spelling errors d. punctuation errors