Which of the following is/are true of a firm targeting a specific debt ratio? [Assuming βB = 0 ]
I. Rₛ​ = R₀ + SB​(R₀ − RB​)
II. Rₛ ​= R₀​ + SB​(1 − t)(R₀​ − RB​)
III. βₛ​ = (1 + SB​)β

A.​ III only
B. I and II
C. I only
D. I and III
E. II and III