Question

an electron dot diagram displays..
19
the number of protons present in an element
how many electrons an element has
all of the above
a symbol, and dots representing valence electrons

Explanation:

An electron - dot diagram (also known as a Lewis dot diagram) uses the chemical symbol of an element (to represent the nucleus and inner - shell electrons) and dots around the symbol to represent the valence electrons.
The number of protons is given by the atomic number (not shown in an electron - dot diagram). The total number of electrons in an atom is equal to the number of protons (for a neutral atom), but an electron - dot diagram only shows valence electrons.

Answer:

A symbol, and dots representing valence electrons.