Final answer:
The correct piece of equipment for collecting objective data from a patient with a swollen left elbow is a goniometer, which measures joint angles and movement.
Step-by-step explanation:
When a patient presents with a swollen left elbow and requires an objective assessment, the medical professional should utilize a goniometer. A goniometer is a tool designed specifically to measure the range of motion in a joint, which is crucial when evaluating conditions such as swelling, injury, or arthritis. Among the options provided:
- Magnifier - Used for magnifying small details, not suitable for assessing joint swelling.
- Blood pressure cuff - Used to measure blood pressure, not joint angles.
- Snellen chart - Used for testing visual acuity, not applicable here.
- Goniometer - The correct choice for measuring joint angles and movement.
Therefore, the correct answer is D) Goniometer, as it is the piece of equipment designed for accurately assessing the degree of swelling or movement in a joint.