Why do sunflowers bloom only in the summer

Answer with explanation:

The genetic composition of the plant defines its structure, they are summer-blooming plants because they need sun and moist steady soil. This plants have adapted to warm temperatures and are not prepared to resist cold, the seeds of the plant are intolerant to cold as well, so this plants better grow in summer or warm climates places, the season the sunflower is planted will affect its development, furthermore, the soil needs to be steady to resist the weight of the plant ones it grows otherwise the plant will die short after blooming, this is the reason the plants grow in American summer, It is sunny, warm and has a steady soil.

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.