Concept:
The endocrine system is a network of glands that produce and secrete hormones.
Hormones regulate many body functions such as:
• Growth and development
• Metabolism
• Reproduction
• Stress response
Major endocrine glands include:
• Pituitary gland
• Thyroid gland
• Adrenal gland
• Pancreas
Step 1: Analyze option A.
Bones belong to the skeletal system, not the endocrine system.
Hence, option A is incorrect.
Step 2: Analyze option B.
Skin and touch are related to the integumentary and sensory systems.
Hence, option B is incorrect.
Step 3: Analyze option C.
The endocrine system mainly consists of glands that secrete hormones.
Hence, option C is correct.
Step 4: Analyze option D.
Eye sight is related to the visual and nervous systems.
Hence, option D is incorrect.
Therefore, the correct answer is:
\[
\boxed{(C)\ \text{Glands and Hormones}}
\]