**Core Concept**
The question tests the understanding of DNA base pairing rules, where adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G). This fundamental principle is crucial in molecular biology for understanding DNA replication and transcription.

**Why the Correct Answer is Right**
To find the complementary sequence, each base in the given sequence (5' TTAAGCTAC 3') is paired with its complementary base. Using the base pairing rules, T is paired with A, A is paired with T, and so on. Thus, the complementary sequence of 5' TTAAGCTAC 3' would be 3' AATTGATGT 5' when applying these rules sequentially.

**Why Each Wrong Option is Incorrect**
**Option A:** This option does not correctly follow the base pairing rules for the entire sequence provided.
**Option B:** Similar to Option A, it does not accurately represent the complementary sequence based on the standard base pairing rules.
**Option C:** This option also fails to correctly apply the base pairing rules to the given DNA sequence.

**Clinical Pearl / High-Yield Fact**
Remembering the base pairing rules (A-T and G-C) is crucial for understanding genetic processes. A common mnemonic to remember this is "A-T" and "G-C" as "Adam Takes Gina to Church" or a similar mnemonic that helps in recalling these rules.

**Correct Answer:** D. 3' AATTGATGT 5'