7. Which of the following is a difference between the shoulder girdle and pelvic girdle? a. The pelvic girdle connects to the axial skeleton, whereas the shoulder girdle does not. b. The shoulder girdle connects to the axial skeleton, whereas the pelvic girdle does not. c. The pelvic girdle is rigid, whereas the shoulder girdle is light and capable of great mobility. d. The shoulder girdle is rigid, whereas the pelvic girdle is light and capable of great mobility.

To determine the correct answer, let's analyze the differences between the shoulder girdle and the pelvic girdle based on their anatomical features and functions. 1. **Connection to the Axial Skeleton:** - The **pelvic girdle** connects to the axial skeleton at the sacrum, forming a strong and stable connection. - The **shoulder girdle** (or pectoral girdle) connects to the axial skeleton via the clavicles, but it is not as rigidly connected as the pelvic girdle. 2. **Mobility and Rigidity:** - The **pelvic girdle** is designed for stability and support, making it more rigid. It supports the weight of the upper body and provides a base for the lower limbs. - The **shoulder girdle** is lighter and allows for a greater range of motion, facilitating the mobility of the upper limbs. Now, let's evaluate the options: a. **The pelvic girdle connects to the axial skeleton, whereas the shoulder girdle does not.** - This statement is incorrect because the shoulder girdle does connect to the axial skeleton, albeit in a less rigid manner. b. **The shoulder girdle connects to the axial skeleton, whereas the pelvic girdle does not.** - This statement is also incorrect because the pelvic girdle does connect to the axial skeleton. c. **The pelvic girdle is rigid, whereas the shoulder girdle is light and capable of great mobility.** - This statement is correct. The pelvic girdle is indeed rigid, and the shoulder girdle is light and allows for a wide range of motion. d. **The shoulder girdle is rigid, whereas the pelvic girdle is light and capable of great mobility.** - This statement is incorrect because the shoulder girdle is not rigid; it is designed for mobility. Based on this analysis, the correct answer is: **c. The pelvic girdle is rigid, whereas the shoulder girdle is light and capable of great mobility.**