Answer: Utility value
Step-by-step explanation: In simple words, utility value refers to the level of satisfaction an individual gets when he or she chooses one alternative over the other. It is the usefulness of a particular commodity for a particular consumer.
In the given case, Laura decided to pursue law instead of medicine because she liked it more, that is, she thinks that she will get more satisfaction from law rather than medicine.
Hence we can conclude that the key factor was utility cost.