In which of the following conditions, the whole incidence of tax lies on the sellers?

By Dalton's tax incidence formula $\frac{\text{Incidence on Buyers}}{\text{Incidence on Sellers}} = \frac{e_s}{e_d}$, the entire incidence of a tax falls on the sellers (zero shifting to buyers) when demand is perfectly elastic ($e_d = \infty$) and/or supply is perfectly inelastic ($e_s = 0$).