Dear Harsh,

Number of pi bonds can vary according to the structure. We can make the structure of C6H10 contating triple bond and also containing double bond.

If the structure contains triple bons then it will have 2 pi bonds.

If it has two double bonds then it will contain 2 pi bonds

If the structure has one double bond, then it will contain 1 pi bond.

So, the number of pi bonds can vary according to the structure.

Good luck!