Which of the following best defines the term 'antioxidant' in the context of biological oxidative stress?

Products like probiotic yogurts or omega-3–enriched eggs, which are promoted for health effects beyond their standard nutrient profile, are examples of:

A diagram shows a molecule with an unpaired electron on an oxygen atom (a radical). Why is this unpaired electron responsible for increased chemical reactivity toward DNA and proteins?

A vegetarian consumes meals totaling 15,000 μg of dietary beta-carotene in one day. Using the conversion 12 μg dietary beta-carotene = 1 μg RAE, calculate the RAE consumed and determine whether this satisfies a female adult RDA of 700 μg RAE. Show your work.

Given a client with limited budget and low fridge space, which meal plan adjustment is the best evidence-based recommendation to maintain antioxidant variety while minimizing cost and spoilage?