For lower bandwidth applications . . . . . . . .

Single mode fiber is advantageous
Photonic crystal fibers are advantageous
Coaxial cables are advantageous
Multimode fiber is advantageous

The correct answer is: C. Coaxial cables are advantageous.

Coaxial cables are advantageous for lower bandwidth applications because they are less expensive than other types of cables, such as single mode fiber and photonic crystal fibers. They are also easier to install and maintain.

Single mode fiber is a type of optical fiber that has a very small core diameter. This allows it to carry more light than multimode fiber, which has a larger core diameter. However, single mode fiber is also more expensive than multimode fiber.

Photonic crystal fibers are a type of optical fiber that has a periodic structure in its core. This structure allows it to carry more light than single mode fiber and multimode fiber. However, photonic crystal fibers are also more expensive than single mode fiber and multimode fiber.

Coaxial cables are made up of a central conductor surrounded by a dielectric insulator. The dielectric insulator is surrounded by a conductive shield. This construction helps to protect the signal from electromagnetic interference.

Coaxial cables are used in a variety of applications, including telecommunications, cable television, and computer networking. They are also used in some industrial applications.

Here is a table that summarizes the advantages and disadvantages of each type of cable:

| Type of cable | Advantages | Disadvantages |
| — | — | — |
| Single mode fiber | Can carry more light than multimode fiber | More expensive than multimode fiber |
| Multimode fiber | Less expensive than single mode fiber | Can’t carry as much light as single mode fiber |
| Photonic crystal fiber | Can carry more light than single mode fiber and multimode fiber | More expensive than single mode fiber and multimode fiber |
| Coaxial cable | Less expensive than single mode fiber, multimode fiber, and photonic crystal fiber | Can’t carry as much light as single mode fiber, multimode fiber, and photonic crystal fiber |

I hope this helps! Let me know if you have any other questions.