If reference bit $=0$ and modify bit $=0$, page is not recently used and not modified, so it is the best page to replace.

If reference bit $=0$ and modify bit $=1$, page is not recently used but modified, so it must be written out before replacement.

If reference bit $=1$ and modify bit $=0$, page is recently used and clean, so it will probably be used again soon.

If reference bit $=1$ and modify bit $=1$, page is recently used and modified, so it will probably be used again soon and needs to be written out.

So,

A → III
B → I
C → IV
D → II

Correct option is:

$\boxed{(d)\ A-III,\ B-I,\ C-IV,\ D-II}$