Respuesta :
The category that needs the most improvement in this paragraph is option D: Spelling and Grammar.
What do you mean by Grammar?
The term grammar in a English language include the structure of language or languages in general.
The improvement include, During El Niño years, however, due to changes in PRESSURE and the direction of trade winds, the surface layer of warm water are thicker and PREVENTS the usual effective upwelling by the COASTAL winds.
The term "upwelling" in this paragraph defined as a situation happens at the time when cold water from the deep get up toward the ocean's surface.
Through this excerpt, the author define the usual days of cold weather which starts from the activity of upwelling and ends up to the coastal winds.
The options A, B and C does not required any change or modification as they are correct.
Therefore, correct option is D.
Learn more about upwelling, refer to the link:
https://brainly.com/question/27943964
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