Final answer:
The last meal likely consisted of cereal with milk and coffee because caffeine is present in coffee, starch in cereal, and fat in milk.
Step-by-step explanation:
The autopsy revealed that the stomach of the deceased contained traces of caffeine, starch grains, and fat.
Given these findings, the most likely composition of the last meal eaten by the deceased is a) Cereal with milk and coffee.
Caffeine is commonly found in coffee, starch is a major component of cereal, and fat could come from the milk added to the cereal.
This combination of substances aligns with the contents discovered during the autopsy.