The definition given — "the art and science of good eating and drinking" — exactly matches the meaning of gastronomy. This term refers to the study and practice of preparing and appreciating good food.
Option (B) "Osteopathy" is a form of alternative medicine focusing on physical manipulation of muscles and bones, unrelated to food.
Option (C) "Gluttony" means excessive eating and drinking, often with a negative moral implication, not the refined art of eating well.
Option (D) "Cooking" refers simply to the act of preparing food, lacking the cultural and scientific aspect implied by "gastronomy."
Therefore, (A) "gastronomy" is correct as it fully captures the concept in the sentence.