Which of the following is the Power Set of {a}\{a\}{a}?
{a,{a}}\{a, \{a\}\}{a,{a}}
{∅,a}\{\emptyset, a\}{∅,a}
{∅,{a}}\{\emptyset, \{a\}\}{∅,{a}}
{{a}}\{\{a\}\}{{a}}