Answer:
C) respalda a traves de datos comprobables la eficacia del producto
Explanation:
The underlined part is "<u>28,4%en la elasticidad y firmeza de la piel</u>" or "<u>a 28.4% increase in elasticity and firmness of the skin</u>".
In the context, the sentence is talking about a anti stretch cream called as EUCERIN ANTI-STRETCH CREAM. It says that if women use the cream for about eight weeks, they will get a good skin tolerance and it is clinically proven that there is increase in elasticity and firmness of the skin by about 28.4% after using this anti-stretch cream.
Thus this shows the effectiveness of the cream and they have also provided a verifiable data along with it which is verified and proven in chemical testing of the cream.
