AIIMS 2019 Physics Half-life MCQ Question

The equation $2^n = 100$ implies that $n$ represents the number of half-lives, and solving for $n$ gives $n \approx 6.64$, which lies between 6 and 7. Therefore, the radioactive element will decay between 6 and 7 half-lives, making option A (6) the most accurate representation of the lower bound. Options B (7) and C (6.5) are incorrect as they do not accurately reflect the calculated range, while option D (6.7) is also not precise enough to represent the lower limit of the decay range.