ID stands for?

• A. Intradigital.
• B. Intradermal.
• C. Intramuscular.
• D. Intravenous.

Answer: (B)

The main idea here is understanding medical shorthand for where an injection goes. ID stands for intradermal, which means the medicine is injected into the dermal layer of the skin—just under the surface. The prefix intra- means within, and dermal relates to the skin, so this route stays very shallow and is used for skin-based tests that rely on a local reaction, like the tuberculin skin test or some allergy tests. Other phrases describe injections into deeper tissues: into a finger would be intradigital, into muscle is intramuscular, and into a vein is intravenous. So intradermal specifically targets the skin layer, not muscle or vein.