Which of the following is an example of a quantitative trait?

The correct response identifies crop yield as an example of a quantitative trait due to its measurement being influenced by multiple genetic and environmental factors. Quantitative traits are those that can be measured on a continuous scale and typically show a range of phenotypes, such as height, weight, or yield, which are not simply categorized into discrete types.

Crop yield is influenced by various parameters such as plant density, nutrient availability, water supply, pest and disease pressure, and genetics. These traits can be quantitatively assessed, as they can vary in degree rather than being classified into distinct categories.

In contrast, traits like flower type or pod shape are often binary or categorical – they do not exhibit the same range of continuous variation. For example, a flower might be classified as a particular color or shape without a gradient scale, making it more of a qualitative trait. Stem length could be considered quantitative, but yield is a more significant example of a trait that integrates multiple factors and demonstrates the essence of quantitative measurement in plant science. Thus, crop yield serves as a prime example of a quantitative trait in this context.