Which of the following best describes the action of photosynthesis inhibitors?

Photosynthesis inhibitors specifically target the photosynthetic process within plants. These herbicides disrupt the ability of plants to conduct photosynthesis by inhibiting key enzymes or processes involved in converting light energy into chemical energy. By doing so, these inhibitors effectively reduce the plant's ability to produce food, ultimately leading to its demise.

The other options describe different mechanisms of action. For instance, preventing amino acid synthesis relates to another class of herbicides that interfere with the plant's ability to build necessary proteins. Disrupting cell membranes refers to herbicides that cause cell lysis, affecting the integrity of plant tissues. Promoting cell division is not a mechanism associated with herbicides, as herbicides typically aim to inhibit or kill plant growth rather than encourage it. Therefore, the action of photosynthesis inhibitors is uniquely tied to their role in obstructing the photosynthetic process.