Answer key to reinforcement exercise available for free at: https://www.biologycorner.com/worksheets/reinforcement-evolution.html ( I've included the student version with this document for convenience. )
The main part of the document focuses on vocabulary, students match a description to words on a list. The last set of questions ask students to explain how evolution occurred in populations of rock pocket mice, elephants, and finches.
Be advised that the last questions are based on specific examples we use in class to show how evolution occurs: rock pocket mice and elephant tusks. Links to lessons for these examples are included in the document.