The plants growing high in the tree canopy send out roots. the roots are searching for water vapor in the humid air of the forest. this response that aerial plants find water is called
a)germination
b)hydrotropism.
c)phototropism.
d)thigmotropism.

B. Hydrotropism

The response that helps aerial parts of the plant to find water is called as hydrotropism. Tropism refers to the response of the plant growth towards a particular stimuli, such as gravity, sunlight, touch and water. The hydrotropism refers to the growth response of the plant parts towards water. The plant may show positive or negative hydrotropism. A positive hydrotropism refers to the response in which the plant grows towards water whereas the negative hydrotropism refers to a response in which the plant grows away from it.

In the given condition, the plants growing high in the tree canopy send out roots. The roots will absorb the water present in the humid air. Therefore, it is a positive hydrotropism response.

the correct answer is option d.

an appositive is a noun, noun phrase or noun clause which follows another noun or noun phrase in order to describe it or name it another way. they are usually used between commas, brackets or dashes.

the example sentence with the correct use of commas is the following:

her uncle, the man over there in the red shirt, owns the hardware store in town.