Answer:
d) 5 m
Step-by-step explanation:
Barrages could be built on the ebb side, or flood side, or even both, to produce electricity. Tidal height can vary from location to location over a broad range (4.5-12.4 m). For profitable operations and adequate water head for the turbines, a tidal range of at minimum 7 m is needed.
So, the appropriate option for the given situation is d.