Tu because If you put Mi or mis son rojos it says my are red which dosen't really make sense. Since you put tu in front of son (plual) it would be they are red.
Answer:
El fútbol es más divertido que el baloncesto.
La paella es más sabrosa que la pizza.
Boston es una ciudad más interesante que Nueva York.
Explanation:
A comparative adjective is an adjective that expresses a comparison of qualities between two elements.
In traditional Spanish grammar, three comparative degrees are contemplated:
Comparison of superiority: in Spanish, más ... que
Comparison of equality: in Spanish, tan ... como
Comparison of inferiority: in Spanish, menos ... que
