When he was very young, William took an intelligence test as part of a research study. Decades later, William is asked if he would be willing to take another intelligence test in order to test the stability of intelligence. By agreeing to take another intelligence test, William is engaging in a(n) study.

if you have to make a general question and respond to your thoughts, then this isn't really a question someone can you on. read the passage, form your question, and answer using your thoughts. no one else can understand how you interpreted this text if you don't tell us.

answer; silence;

answer; randomization;