Which of the following is an example of a plant responding to the external stimulus of gravity? A.) A seedling growing toward a sunny window
B.) A plant root growing down into the soil
C.) Flowers producing nectar to attract bees
D.) a potted plant wilting when it dries out

b

Explanation:

bcs the root grows towards the gravity

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs

the answer is c.mitochondria. glad to .