When the effective pressure is smaller than pre-consolidation pressure, the final settlement is ____________

• A. \(ρ_f=Hlog_{10} \frac{σ’}{σ’_0}\)
• B. \(ρ_f=H \frac{C_c}{1+e_o} log_{10} \frac{σ’}{σ’_0}\)
• C. \(ρ_f=H \frac{C_S}{1+e_o} log_{10} \frac{σ’}{σ’_0}\)
• D. \(ρ_f=H \frac{1}{1+e_o} log_{10} \frac{σ’}{σ’_0}\)