In practice the TMO 1 mode usually is the 1st choice because

In practice, the TMO 1 mode usually is the 1^st choice because: It is the dominate mode. It has lower conduction loss. Many countries adopted the convention. Its field pattern is very close that of the TEM mode in the coaxial cable.

Solution

Option d. Its field pattern is very close that of the TEM mode in the coaxial cable.