Jamille is taking french in school. she gets her best grades on vocabulary tests if she studies for 15 minutes every day for 8 days than if she crams for 2 hours the night before the test. this illustrates what is known
a. the spacing effectb. massed practicec. the testing effectd. chunking

a. the spacing effect                                                                                                          

Explanation:                            

The spacing effect: In psychology, the term spacing effect was first introduced by a German psychologist named Hermann Ebbinghaus, and is defined as the phenomenon which suggests that the long-term memory of an individual is increased when the learning related to different events are being spaced apart in interval of time instead of occurrence in immediate succession.

Example: Remembering items in a list.

In the question above, the given statement illustrates the spacing effect.

answer; collective security;