This question is important for competitive exams like SSC, UPSC, Banking, and other government exams. Understanding this concept will help improve your accuracy and performance in real exams. Practice similar MCQs regularly to strengthen your preparation and boost your score.
Correct Answer: Cunning
A. Substantial: Large or important in amount.
B. Unstable: Not steady or secure.
C. Instantaneous: Happening immediately.
D. Cunning: Deceptive and harmful in a subtle, hidden way.
Insidious → In-side hide → hidden harmful danger.