Juke Provided Smiles Contingent on His Grandfather's Spontaneous Remarks

Juke provided smiles contingent on his grandfather's spontaneous remarks. What were the independent (IV) and dependent variables (DV) ?

A) The DV was the contingent smiles and the IV was the spontaneous remarks
B) The DV was the spontaneous remarks and the IV was the contingent smiles
C) The DV was Juke and the IV was his grandfather
D) The IV was Juke and the DV was his grandfather