Wax meaning in the sense of growth is to:

• A. To become stronger
• B. To put wax on a surface
• C. To express oneself
• D. To get larger or increase in size

Answer: (D)

Wax in the sense of growth means to get larger or increase in size or amount. This sense comes from the idea of things growing over time, like the moon becoming fuller or interest and populations increasing. The best choice directly expresses that idea of growth in size. The other meanings refer to coating a surface with wax or to speaking in a long, expressive way, which aren’t about growth in size. For example, you’d use this sense when saying the moon waxes, or public interest waxed, to indicate it grew or expanded.