Answer:
The correct answer will be options-
1. Beak depth and length must show variation among individuals of a single species
2. Over time, individuals can evolve to better fit the environment by changing heritable traits
3. Beak depth and length must affect survival and/or reproduction of birds.
Explanation:
Charles Darwin studied the birds of the Galapagos island and concluded that organisms evolve with time by showing natural adaptation as a mechanism.
In 1973, Grants went to the Daphne major and live on the island and observed the finches for about 40 years or more visiting the place repeatedly.
His finding helped him conclude that individual can evolve by changing the traits which become heritable, the beaks showed variation in the individuals of the same species and the size of the beak affects the survival and reproductive rate of the birds.
Thus, the selected options are correct.