The best answer is choice C) because "other" tells us that "water" is a resource, and not separate from resource management.
___________________________ will be at the head of the legislature's list of concerns for the coming session.
(C)
Problems in the management of water and [in the management of]
other resources
Below,
water and
resource management can be interpreted as two separate problems: water, resource management (note, water is a resource), and the reason (A), (B) or (E) is not the best choice:
(A) Water and resource management problems
(B)
Problems of managing water and resources

(E) Resource management problems,
including water
As for (D), the phrase
other resource management is fragmented. It needs a noun; e.g.,
other resource management issues:
(D) Problems of water and
other resource management 