Referring to the pending supreme court ruling, bank owners often expressed frustration that their ability to seize market opportunities is being hampered by excessively strict regulations.

A
Referring to the pending supreme court ruling, bank owners often expressed frustration that
B
With reference to the pending supreme court ruling, bank owners often expressed frustration that
C
In reference to the pending supreme court ruling, bank owners often expressed frustration about
D
When referring to the pending supreme court ruling, bank owners often express frustration about
E
Referring to the pending supreme court ruling, bank owners often express frustration that

OA : after some discussion