Which of the following is not true of the deadweight loss from a small commodity tax?

(a)It is zero if the demand curve is completely inelastic.

(b) As the tax rate is increased, the deadweight loss also increases, but at a slower rate.

(c) It measures a loss in revenue relative to a lump-sum tax that causes the same decline in utility.

(d) It can be represented by a triangle under a demand curve.