Most products are adding to their improvement.

the average project portfolio

The statement "Most products are adding to their improvement" suggests that there is a general trend among products to enhance their features, performance, or user experience. This could be through technological advancements, design improvements, or additional functionalities. The term "average project portfolio" implies a collection of projects that represent a typical or standard set of products or services. Therefore, the correct answer implies that the majority of products in an average project portfolio are undergoing improvements.