If an option says the mantle is entirely liquid what is the strongest counter argument?

Correct answer: S waves pass through many mantle parts and mantle is solid with plastic behaviour

The direct answer is option A: S waves pass through many mantle parts, and the mantle is solid but can behave plastically. A completely liquid mantle would not allow S waves to travel through it, because shear waves require a material that can resist sideways deformation. Earthquake evidence shows that the mantle is predominantly solid. Its rocks can flow extremely slowly under great heat and pressure, so “plastic behaviour” does not mean that the whole mantle is liquid. Option A is correct and gives both the seismic evidence and the correct physical description. Option B is wrong because the mantle lies inside Earth, below the crust, not in the atmosphere. Option C is wrong because it is made mainly of hot silicate rocks and minerals, not sea water. Option D is wrong because P waves do enter and travel through the mantle. The core may have liquid and solid parts, but that fact must not be wrongly applied to the entire mantle. Memory cue: S waves need rigidity; mantle is solid, hot, and slowly flowing.