urgent help, 2 BBS dollar

In the IS-LM model, a decrease in expected inflation will cause:
A. a decrease in output
B.a decrease in the nominal interest rate
C.an increase in the real interest rate
D.all of the above
E.none of the above

Please help me to solve the problem, which one should I choose, thank you so much!
The payment is 2 BBS dollars.

C.an increase in the real interest rate