<span>Tú compras un boleto para ellos.
From the options, it appears you need to write this sentence using a direct object pronoun. The object of the sentence is un boleto, which is masculine singular. This means the direct object pronoun must be masculine singular; the direct object pronoun must be lo.
This narrows the options to 1 and 2, however the first option can be eliminated due to grammatical error (los lo, which translates to "the the", doesn't make sense).
Answer:
</span>2) Se lo compras.
Answer:
sorry i did not take spanish class
The theory developed based on observations made on the Galapagos islands was, Natural Selection.
I hope I helped you!
Source: https://socratic.org/questions/which-theory-was-developed-based-on-observations-made-on-the-gal-pagos-islands