The main idea of a text refers to the major point that the writer wants the reader to understand in the text. So, the sentence from “The Secret Lives of Succulents” that best illustrates the central idea of the passage is:
*However, just because they do well with little water does not mean that they can thrive without regular care.*
In this passage, the speaker gives the message that succulents can store more water than cacti. He expounded on the properties of succulents that make them store more water than cacti.
Yet, the main point he makes is that even though succulents can thrive with little water, they still need regular care to thrive.