Question

which angle is adjacent to ∠cfd? ∠efa ∠bfc ∠bfd ∠cfe

Explanation:

Step1: Recall adjacent - angle definition

Adjacent angles share a common side and a common vertex and have no common interior points.

Step2: Analyze each option

For $\angle EFA$, it does not share a common - side with $\angle CFD$.
For $\angle BFC$, it does not share a common - side with $\angle CFD$.
For $\angle BFD$, it shares a common side $FD$ and a common vertex $F$ with $\angle CFD$ and has no common interior points.
For $\angle CFE$, it does not share a common - side with $\angle CFD$.

Answer:

$\angle BFD$