A market gardener uses a paraffin heater in a greenhouse to improve the yield of plants. Which one of the following is not a good explanation for the effect of the heater?

A. The heater produces light for the greenhouse

Correct answer: A. Light is not one of the products of the heater

B. The heater increases the temperature of the greenhouse

C. The heater increases the carbon dioxide in the greenhouse

D. The heater extends the growing season into winter months, which would otherwise be non-productive