<em>Answer:</em>
<em>D. a signal; a chemical; auxin </em>
<em>Explanation:</em>
<em>Phototropism</em><em> is described as a phenomenon that involves the growth of a specific organism as an outcome towards a light stimulus. It is generally observed or found in plants yet occurs in a few other organisms, for example, fungi. The different cells that are being found on the plants that are placed far from the light posses a specific chemical known as 'auxin' that generally reacts when the "phototropism" occurs.</em>
Answer:
A) required a significant increase in military spending. reduced the role of conventional forces.
Explanation:
President Kennedy's "flexible response" strategy met his demand for a wider choice than humiliation or all-out nuclear action
If the manipulation of the independent variable causes a change in the dependent variable, covariance is established.
