What is a mutual benefit bailment?

Select one:

a$.$ an ordinary commercial transaction such as the delivery of goods to a person for repair or an automobile to a paid parking lot attendant

b$.$ Sherry agrees to store Jim's car in her garage for the winter for free.

c$.$ Brenda asks Matt to hold on to her computer while she grabs lunch.

d$.$ Jim lends his car to his neighbor Sherry so she can go to the grocery store.