1) no.
2) el.
3) ellos.
4) esos.
lo siento si me equivoco.
The scenario is likely a dialogue, like this:
<span>A: ¿ __________ el texto de Ana?
B: No, no entiendo para nada.</span>
The person B says that he or she does not understand it, so person A must be asking " do you understand it"?
thre are two ways of asking this: "entiendes" (informal) or "entiende" (formal) - but since the second is not among the options, "entiendes" is the correct answer!
I think the answer is sois

Some examples of communicable diseases are:-
1. Hepatitis A
2. Hepatitis B
3. Ebola
4. Flu