Answer:
Both Options C and D are appropriate.
But I'd go with Option D since "Direct Air Capture" would eventually lead to "Ground Injection"
OPTION D.
When you mix pure water and salt(sodium chloride) you will make a saline solution.
Saline solution with 0.9% concentration is used frequently in the medical field for resuscitation fluid because it will have same molarity with the body fluid, so it won't induce fluid exchange caused by osmosis.