The correct answer is option 'c' - dense fibrous connective tissues.

Explanation:
The cranium, also known as the skull, is the protective bony structure that surrounds and encloses the brain. It consists of several bones that join together to form a strong and rigid structure. These bones are connected to each other by dense fibrous connective tissues, which help to provide strength and stability to the cranium.

Here is a detailed explanation of why dense fibrous connective tissues are responsible for joining the skull bones together to form the cranium:

1. Function of connective tissues:
Connective tissues are a type of tissue that provide support and connect different structures in the body. They consist of cells and an extracellular matrix that contains fibers and ground substance. Connective tissues have various functions, including providing structural support, protecting organs, and connecting tissues and organs together.

2. Types of connective tissues:
There are several types of connective tissues in the body, including loose fibrous connective tissues, dense fibrous connective tissues, specialized connective tissues, and dense irregular connective tissues. Each type of connective tissue has different properties and functions.

3. Dense fibrous connective tissues:
Dense fibrous connective tissues are characterized by a high density of collagen fibers arranged in a parallel fashion. These fibers provide strength and resistance to tension forces. Dense fibrous connective tissues are found in structures that require strength and stability, such as tendons, ligaments, and the outer layer of bones.

4. Role in the cranium:
In the cranium, the dense fibrous connective tissues join the skull bones together at specialized joints called sutures. Sutures are fibrous joints that allow slight movement between the bones during growth and development but become fused and immovable in adulthood. The dense fibrous connective tissues in the sutures help to hold the skull bones firmly together, providing stability and protection to the brain.

5. Importance of strong connections:
The dense fibrous connective tissues in the cranium are essential for maintaining the structural integrity of the skull and protecting the brain from injury. Without these strong connections, the skull bones would be more prone to dislocation or fracture, which could lead to severe damage to the brain.

In conclusion, dense fibrous connective tissues join the skull bones together to form the cranium. These tissues provide strength, stability, and protection to the brain by forming strong connections between the bones at the sutures.