I am thinking the Statue of Liberty
They argued about ratification and how many states would need to agree for the Constitution to take effect is the answer that summarizes the main argument between the Federalists and Anti-Federalists during the Constitutional Convention. The correct option among all the options that are given in the question is the last option.
The Flexible response was a policy implemented by President John F. Kennedy in 1961 in order to substitute the New Look and the massive retaliation policy that Dwight Eisenhower's had introduced, which consisted on responding using a greater force in case of an attack, and such force involved nuclear weapons.
On the other hand, the flexible response policy aknowledges the Mutual assured destruction if nuclear weapons are involved, as the enemy with shoot back too. It aimed to provide a manner of responding to agression across the spectrum of war but without the employment of nuclear weapons.
The biggest tower in the world is the Tokyo Skytree.