Shown Here Are Four Ligands (M, H, K, and L)

Multiple Choice

Shown here are four ligands (M, H, K, and L) and their corresponding receptors along with three genes (U, V, and W) whose activity the receptor controls through signal transduction. The arrows indicate gene activation, the T-bars indicate gene repression. If both U and V are required to activate W, which ligand (or ligands) result in W being active?

A) ligand M
B) ligand H
C) ligand K
D) ligand L
E) None of the answer options is correct.