DrWelsh Is Doing Experiments Using Drugs

question 7

Multiple Choice

Dr.Welsh is doing experiments using drugs.He is concerned that his subjects will respond to demand characteristics.He may want to control for this by using which of the following?

• A)stratification
• B)two independent variables
• C)a placebo
• D)randomization

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Definitions:

Long-day Plant

Plants that flower only after being exposed to light periods longer than a certain critical length.

Sunflower

A large plant belonging to the daisy family, known for its large flowering heads and edible seeds.

Shade Avoidance

A growth response of plants to reduce shading by neighboring plants, often resulting in elongation of stems and leaves to reach light.

Far-red Light

A spectrum of light at wavelengths longer than that of red light, between 700 and 800nm, crucial for plant physiological processes.