This is how to conjugate the verb ESTAR (which means to be) in the present tense:
yo estoy, tu estás, el/ella/Usted está, nosotros estamos, vosotros estáis, ellos/ellas/Ustedes están.
Your sentence is I am home. In Spanish, the word YO stands for I in English. This means that you would use the form estoy in your example.
The correct answer is B. estoy.
“ El muchacho” would be the best choice because it is asking a question and “mañana, dia, and hola” all have a past tense sort if deal to them.
Dinero / money
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Dos cosas buenas acerca de ser un dentista es buen dinero y la conexion a sus pacientes. Dos cosas malas sobre ser un doctor son las largas horas y la educacion larga. Dos cosas es estar ayadando a la gente y el sentido de logro