C. FLOOD STAGE is reached when the water level of a stream or river exceeds its natural banks.
Flood stage is a level at which a body of water's surface has risen to a sufficient level to cause sufficient inundation in areas that are not normally covered by water, causing inconvenience or a threat to life and/or property.
The main reason why some stable ionic compounds have +1 charged ions, even though other higher would have a more favorable lattice energy is because;
1. Energy is required to remove each of the electrons in an atom, and the more more the electrons are removed, the smaller the atom radius becomes, with increasing nuclear attraction between the opposite charges.
Note, it is a bit easy to remove a single electron, when compared to 4, 5 or 6 electrons. hence, the reason why Ionic compounds are more stable with + charged ions than others.
2. The stability of an ionic compound is dependent on his lattice energy. And the ions with large charge will have a greater attraction between the cations and anions, hence have higher lattice energy. However, the distance between the ions and the nucleus of the atom plays a major role in the stability of the ion.