Final answer:
The best option to complete the sentences is 'más que, riquísimas'.
Step-by-step explanation:
The correct option to complete the sentences is:
más que, riquísimas
This option correctly translates to:
I love hamburguers more than salads. I prefer to eat hamburguers because they are very delicious.
This option uses the comparative form of the adjective 'delicious' ('riquísimo') and the comparative structure 'más que'.
Learn more about Comparative forms of adjectives in Spanish