Hello!
This statement is talking about visiting the coast of Patagonia during a trip to Argentina.
Let's translate the given four statements.
1. Es una pena que translates to "It is a shame/pity that".
2. Es triste que translates to "It is sad that".
3. Es recomendable que translates to "It is recommended that".
4. Es injusto que translates to "It is unfair that".
Therfore, the statement that fits in with the missing phrase is C, "es recomendable que".
Es recomendable que visiten la costa de Patagonia durante su viaje a Argentina.
