issb general knowledge MCQ #41

Hardest natural substance?

issb general knowledge MCQ #41

  1. Question 1

    Q1. Hardest natural substance?

    • A) Gold
    • B) Iron
    • C) Diamond
    • D) Granite

    Answer: Diamond

    Explanation: Diamond ranks 10 on Mohs hardness scale. Granite is hard rock but not the hardest material.