Correct Answer - D
P.D. across `R_2=V_z=10 V`
`therefore` P.D. across `R_1` = 15-10 =5 V
`therefore I_(R_2) = 10/1500 = 1/150 A ` and current through `R_1=5/500 = 1/100 A`
`therefore ` Zener current . `I_z=1/100-1/150 = 1/300` A
`therefore I_z=1/300xx1000 ` mA = 3.33 mA