B. - Encuentra
The correct for of "encontrar" that fits the sentence is "encuentra" (él encuentra, he finds).
Hope it helped,
BioTeacher101
C. pupil
." The Spanish word "pupitre" translates to "desk." So who uses a desk? Puppets, puppies, and puddles do not use desks, but pupils do. "Pupil" is a synonym for "student," so clearly, "pupil" and "pupitre" are connected.