Final answer:
The most effective revision of the sentence is: 'The greenhouse is hot and humid, and it is a site for sore eyes starved of color by winter's whiteness because orchids bloom in all the colors of the rainbow and green ferns grow all over.' This revision improves the sentence by providing clearer and more concise information.
Step-by-step explanation:
The most effective revision of the sentence is: The greenhouse is hot and humid, and it is a site for sore eyes starved of color by winter's whiteness because orchids bloom in all the colors of the rainbow and green ferns grow all over.
This revision improves the sentence by providing clearer and more concise information. It also uses proper punctuation and grammar. By mentioning the specific colors of the orchids and the greenery of the ferns, the revised sentence enhances the imagery and paints a vivid picture of the colorful greenhouse.