The correct option is A a=2,b=3
The given figure is of the net of dice.
We know that, the sum of numbers on the opposite faces of dice is 7.
When we will form a dice with the net the number opposite to a will be 5 and the number opposite to b will be 3.
Hence, a + 5 =7
So, a = 7 - 5 = 2
Similarly, b + 4 =7
So, b = 7 - 4 = 3
So, the value of a = 2 and b = 3.