Which element is NOT a suitable means of expression for communicating technical requirements?

Visual aids are indeed a suitable means of expressing technical requirements. They can help convey complex information in a more digestible format and support better understanding through representations such as diagrams, charts, and pictures.

The use of natural language allows for nuanced expression and the ability to capture detailed subtleties in requirements. Templates provide a structure that guides the documentation of requirements, ensuring consistency and completeness. Flowcharts are effective in illustrating processes and workflows, making them valuable for depicting the logical flow of operations or the relationships between different system components.

In contrast, while visual aids are beneficial for enhancing communication, they are not always the primary method of expression for conveying technical requirements, which often requires more thorough articulation that other choices can provide more comprehensively.