Answer:
Bathing suits and sandals
Step-by-step explanation:
Let's analyze the passage and look for key words/hints.
De la estación de tren vamos a pie a la playa: From the train station we are going by foot to the beach.
Jacobo va a ir de pesca y yo voy a caminar por la arena: Jacob is going to fish and I am going to walk in the sand.
Después vamos a nadar, a tomar el sol y a descansar al lado del mar: After we are going to swim, sunbathe and rest by the sea.
Clearly, they are going to the beach. The question asks us what should be packed. If they are going to the ocean, then they should pack bathing suits and sandals.