Correct Answer - Option 3 : 103

**Given:**

A has 135 books of History, B has 165 books Civics and C has 215 books of Geography respectively.

**Calculation:**

Here in the question we have to first find the highest number of stack for all three sets of books.

We need to find the HCF of numbers of books.

Highest common factor of 135, 165, and 215 = 5

Total number of stacks = 135/5 + 165/5 + 215/5 = 103

**∴ The total number of stacks is 103.**