D and F Block Elements

Which of the following statements are correct? (A) The M$$^{3+}$$/M$$^{2+}$$ reduction potential for iron is greater than manganese. (B) The higher oxidation states of first row d-block elements get stabilized by oxide ion. (C) Aqueous solution of Cr$$^{2+}$$ can liberate hydrogen from dilute acid. (D) Magnetic moment of V$$^{2+}$$ is observed between 4.4 - 5.2 BM. Choose the correct answer from the options given below :