Endogenous agonists such as adenosine and prostacyclin,as well as $\beta$ ₂-adrenergic receptor agonists,can elevate cAMP concentration in smooth muscle.The elevation of cAMP in the smooth muscle results in activation of cAMP-dependent signaling pathways in the smooth muscle.This activation typically:

A)Promotes relaxation,partly because of activation of myosin phosphatase.
B)Promotes contraction,partly because of activation of potassium channels.
C)Promotes relaxation,partly because of activation of Rho kinase.
D)Promotes contraction,partly because of inhibition of InsP3 production.
E)Promotes relaxation,partly because of inhibition potassium channels.