A clay layer of thickness \( H \) has a preconsolidation pressure \( p_c \) and an initial void ratio \( e_0 \). The initial effective overburden stress at the mid-height of the layer is \( p_0 \). At the same location, the increment in effective stress due to applied external load is \( \Delta p \). The compression and swelling indices of the clay are \( C_c \) and \( C_s \), respectively. If \( p_0 < p_c < (p_0 + \Delta p) \), then the correct expression to estimate the consolidation settlement \( s_c \) of the clay layer is