Question

a)identify muscle a.
name one action of this muscle.
b)identify muscle b
name one action of this muscle. mention the part or joint acted on

Explanation:

For part A: The trapezius muscle is located in the upper back and neck area. One of its main actions is to elevate the scapula (shoulder blade).
For part B: The external oblique muscle is in the abdominal region. One of its actions is to rotate the trunk (at the spinal joints).

Answer:

A. Muscle A is the trapezius. One action: elevates the scapula.
B. Muscle B is the external oblique. One action: rotates the trunk (at spinal joints).