Correct Answer - Option 2 : 101

**Given:**

4523 + least number = Perfect square

**Calculation:**

Nearest square number to 4,523 is 4,489 and 4624

4,489 is a square of 67,

4,624 is a square of 68

4,489 is smaller than 4,523,

So it is not acceptable.

Least number to be added,

⇒ 4624 – 4,523 = 101

**∴ Least number should be added is 101.**