Which of the following actions best describes "proliferate"?

The term "proliferate" specifically refers to the rapid increase or multiplication of something. In various contexts, it often describes things like the rapid growth of cells, the expansion of ideas, or the spread of technologies. Therefore, choosing an action that conveys a sense of quick expansion aligns perfectly with the meaning of "proliferate."

Other choices do not capture the essence of this term. For instance, "to diminish gradually" implies a decrease, which is the opposite of proliferation. "To simplify" indicates making something easier or less complex, which does not relate to the idea of increasing or spreading. Similarly, "to analyze deeply" suggests a thorough investigation or examination rather than an action that signifies growth or multiplication. Thus, the best description of "proliferate" is to "expand quickly," reflecting its inherent meaning of rapid increase.