Pharmacology Which of the following is true for receptor action of a drug: A An antagonist has both intrinsic activity and affinity for receptor B An antagonist has affinity but no intrinsic activity for receptor C A partial antagonist has no intrinsic activity or affinity for receptor D Intrinsic activity and affinity are not important for drug action 💡 Explanation Which of the following is true for receptor action of a drug: ✓ Correct Answer: B. An antagonist has affinity but no intrinsic activity for receptor