Seven persons Az, Bz, Cz, Dz, Ez, Fz and Gz are sitting

Solution

According to the given conditions,  Two persons are sitting between Bz and Gz and Dz sits third to the right of Bz.  Bz sits 3rd to the right of Gz.  Since Az sits second to the left of Ez and Cz is the neighbor of Gz, from these conditions we get that Cz sits to the immediate right of Gz and Ez sits just to the left of Dz.  Now only Fz remains, who must be sitting to the right of Bz. Final arrangement is shown below. From the above arrangement, it is clear that: Fz sits to the immediate left of Dz. So, statement I is true. Also, two persons sit between Gz and Ez. So, statement II is also true. Hence, the correct answer is (B).