When Amanda had to memorize the names of Piaget's four stages of cognitive development—sensorimotor, preoperational, concrete operational, and formal operational—she took the first letter of each word and made the following sentence: Some People Can Fly! This helped her learn the names of the stages of cognitive development. In this scenario, which of the following strategies did Amanda use to memorize the information?
a. Acronym
b. Visualization
c. Chunking
d. Acrostic