Mary manages a balanced portfolio at BONDCO, with a mandate of holding $60\%$ equities and $40\%$ bonds. Mary heard from CIMCO's Chief Economist that he believes that the Fed will raise interest rates by more than $150$bps and, as a result, bond yields will rise by the same amount accross $($an upward parallel shift$)$ the yield curve$).$ Based on this call, how should she prepare CIMCO's balanced portfolios to higher bond yields? $($Mark the only CORRECT answer$)$

a$.$

Reduce the duration D$*$ of the portfolio

b$.$

Increase the share of bonds that have low coupons and long maturities

c$.$

Increase the duration D$*$ of the portfolio

d$.$

Increase the share of bonds wB in the total portfolio