I am thinking the correct answer among the choices presented is option D. The sentence that does not properly use a subordinating conjunction is "He acts like he's going to cry". This is because it does not have any joining of clauses in the sentence.
There's who, what, when, where, and why.
Who: Town Council
What: Special Meeting
When: July 12
Where: Central High
Why: ____
Therefore, "why" is the missing "W"
B. Just one of the detail sentences