While plants use all wavelengths of visible light for photosynthesis, red and blue light are the most efficient for producing glucose. Here's why:

* Red light is absorbed by chlorophyll, the pigment responsible for photosynthesis. This absorption triggers the chemical reactions that convert light energy into chemical energy in the form of glucose.

* Blue light is also absorbed by chlorophyll and plays a crucial role in regulating plant growth and development. It influences processes like stem elongation, leaf formation, and flowering.

Together, red and blue light provide the optimal spectrum for photosynthesis, resulting in the highest production of glucose.

It's important to note that while green light is reflected by chlorophyll, it still contributes to photosynthesis to a smaller degree. Plants use all wavelengths of visible light, but red and blue are the most efficient for glucose production.