What would be the gray code equal to the number 14 ?

Correct option is D

​$$\text{Let the input to the circuit be 14} \\ \text{Binary value of 14 is } 1110 \\ \\ \therefore \text{For an input } 1110, \text{ we get the output as:} \\ y_1 = 1 \\ y_2 = 1 \oplus 1 = 0 \\ y_3 = 1 \oplus 1 = 0 \\ y_4 = 1 \oplus 0 = 1 \\ \\ \text{Hence the gray code for 14 is } 1001$$​​