You own a beachfront lot that has been experiencing erosion due to beach starvation. your neighbor to the north (up-current) has the same problem, so he gets permission to build a groin just north of your property line. your response would probably be to
a. armor your shoreline with a full-length seawall
b. get permission to build a groin of your own near the southern boundary of your property
c. do nothing, as the situation will stabilize with time and the sand will come back
d. sue your neighbor for sand deprivation
e. have sand trucked in to rebuild your beach