Food for Families, a nonprofit organization, uses inputs such as money, groceries, volunteer time, and labor to transform food into hot, prepared meals for needy families. In this setting, which of the following is a transformation process?

a. traveling abroad to find less expensive ingredients
b. giving families raw ingredients and expecting them to prepare meals themselves
c. tasting the meals to make sure they are satisfactory
d. fundraising and promoting the cause to gain new volunteers and food donations
e. paying rent for a cooking facility