Aresearcher gives participants a list of words referring to concrete objects (e. g., car, apple, box). she tells the first group of participants to form a vivid mental image of each object. she tells the second group to think of a story using all the words from the list. both groups then completed a memory test. what concept is the researcher most likely testing with the first group of participants? a. semantic encoding b. visual encoding c. acoustic encoding d. simultaneous encoding