R22 Question 6 only, someone, because, overall

DoubleDip

Can someone explain why the answer to Reading 22 Question 6 is C? I thought the answer was A because shifting some pension assets from equity to fixed income would mean less overall shareholder equity risk. Less shareholder equity risk leads to higher market value of equity and thus a lower D/E. You debt doesn't change if you move pension assets from equity to FI, so I thought only the E in D/E would change.

Thanks.