Critical Reasoning (CR) | In the late nineteenth century, the archaeologist Charles

This one is actually easy if you diligently follow POE(process of elimination)
Clearly it says -hidden assumption.

What is the hidden assumption underlying Prof. Zweig's hypothesis?
A) The specific weight of water and earth are similar, thus creating the same pressure on the tunnel's ceiling. -sounds Ok
B) Otherwise inaccessible sunken archeological artifacts can be reached using new technological advancements in the world of marine robotics. -weakens
C) Tunnels beneath the seafloor and tunnels
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