**Question**

**Which of the following numbers replace the question mark?**

A) 9

B) 1

C) 6

D) 2

**Answer: **C

**Solution:**

The number given in the triangles are in a sequence i.e.,) the numbers in the 1st triangle are 1, 2, 3, 4.

The numbers in the 2nd triangle are 2, 3, 4, and 5.

Similarly, in the 3rd triangle, the numbers must be 3, 4, 5, and 6

∴ The required number is **6**.