Answer:
In the above mentioned scenario, Sonia uses the rhetorical appeal of Logos.
Explanation:
There are basically three types of rhetorical appeals: Ethos, Pathos, and Logos. In the above mentioned example, Sonia hava made use of Logos appeal to persuade the undergraduate students.
Logos is an appeal where the person try to convince its audience by the use of logic or reason. Sonia uses logos by presenting her theorems which means a true and factual statement accepted and proved by mathematical operations to the students.
