Laura: Eva es muy simpática, ¿__________?
Marc: Sí, ella es muy simpática.
Translation:
Laura: Eva is very nice, [blank]?
Marc: Yes, she is very nice.
The options
A. por lo tanto - thus
B. nada - nothing
C. ninguno - none
D. no es cierto - is it not true
From Marc's reply to Laura, we can tell she's asking whether he agrees with her. The option that makes the most sense is no es cierto; it is the Spanish equivalent to "wouldn't you say?".
Answer:
D. no es cierto