Correct option is B
Given: Chair: 4921019 :: Mobile:?

EXPLANATION:
C POSITION VALUE 3+1=4
H POSITION VALUE 8+1=9
A POSITION VALUE 1+1=2
I POSITION VALUE 9+1=10
R POSITION VALUE 18+1=19
By adding 1 to the position of the alphabet, now we get
chair: 4921019
M POSITION VALUE 13+1=14
O POSITION VALUE 15+1=16
B POSITION VALUE 2+1=3
I POSITION VALUE 9+1=10
L POSITION VALUE 12+1=13
E POSITION VALUE 5+1=6
By adding 1 to the position of the alphabet, now we get
Mobile: 1416310136