The abbreviation for the term that means pertaining to through the skin isSelect one:a.TD.b.ID.c.I&D.d.derm.

Step 1: Break Down the Problem

To solve this multiple-choice question, we need to identify the correct abbreviation related to the term that means "pertaining to through the skin."

Step 2: Relevant Concepts

1. TD: This often stands for "transdermal," which does relate to administration through the skin.
2. ID: This stands for "intraderma," which also pertains to the skin but specifically indicates within the skin layers.
3. I&D: This means "incision and drainage," which does not pertain specifically to through the skin.
4. Derm.: This refers to "dermato," relating to skin but not specifically through it.

Step 3: Analysis and Detail

• TD (Transdermal): This is directly used for processes that involve moving substances across the skin barrier.
• ID (Intradermal): Close but signifies within the skin itself rather than through it.
• I&D: Not relevant to the question's focus on "through the skin."
• Derm.: General skin reference, does not imply through the skin specifically.

Step 4: Verify and Summarize

Among the choices, the most appropriate term that signifies "pertaining to through the skin" is "TD" for transdermal.

Final Answer

The correct abbreviation is a. TD.