Final answer:
The best tener expression is 'Tengo hambre' which means 'I am hungry'.
Step-by-step explanation:
The best tener expression that corresponds to the given sentence is Tengo hambre. This translates to 'I am hungry'. The sentence 'Escalo las montañas todos los días. Como arroz y pollo, pero hoy no tengo comida en mi mochila.' means 'I climb mountains every day. I eat rice and chicken, but today I don't have food in my backpack.'
Learn more about Tener expressions in Spanish