What step is necessary in ensuring the validity of operationalization of experimental treatments (or independent variables)?

Listening begins with _____ messages the speaker sends

A) responding to B) evaluating C) understanding D) receiving

Because of his family's medical history, Malik decided to give his informative speech on sickle-cell anemia. When he finished work on the speech, it had the following main points.I. Sickle-cell anemia is a hereditary blood disease caused by abnormal blood cells.II. The effects of sickle-cell anemia include liver damage, blindness, paralysis, and early death.Malik's main points were arranged in ________ order.

A. topical B. formal C. medical D. causal E. analytical