Given an initial value problem based on an ordinary differential equation (ODE), which specific formulas express yₖ₊₁ in terms of yₖ associated with a second-order Taylor series method?

a. yₖ₊₁ = yₖ+h⋅f(yₖ,yₖ′)+h²/2⋅f′(yₖ,yₖ′)
b. yₖ₊₁ = yₖ+h⋅f(yₖ,yₖ′)+h²/2⋅f(yₖ,yₖ′)
c. yₖ₊₁ = yₖ+h⋅f(yₖ)+h²/2⋅f′(yₖ)
d. yₖ₊₁ = yₖ+h⋅f(yₖ)+h²/2⋅f′(yₖ′)