Choose the most appropriate option to change the voice (active / passive) form of the given sentence.
I owe a big debt of gratitude to my mentor, Ms. Pallavi Dutta.

A

A big debt of gratitude had been owed by me to my mentor,Ms. Pallavi Dutta.

B

A big debt of gratitude was owing by me to my mentor,Ms. Pallavi Dutta.

C

A big debt of gratitude will be owed by to my mentor, Ms. Pallavi Dutta.

D

A big debt of gratitude is owed by me to my mentor, Ms Pallavi Dutta.