Question

which angle is adjacent to ∠bdc? ∠adc ∠cdb ∠adb ∠cda

Explanation:

Step1: Recall adjacent - angle definition

Adjacent angles have a common vertex and a common side.

Step2: Analyze the given angles

For $\angle BDC$, it has vertex $D$. The angles with vertex $D$ that share a side with $\angle BDC$ are considered. $\angle ADB$ shares side $DB$ with $\angle BDC$ and has the common vertex $D$.

Answer:

$\angle ADB$