Correct Answer: BCDA

Solution : The correct choice is the first option.

Explanation:
The order BCDA presents a logical progression of information related to the importance of vitamins and minerals in supporting the immune system and flu prevention. It begins with Vitamin C ( B) , highlighting its vital role in maintaining the body's natural defence. This is followed by a broader statement about combining various vitamins and minerals, including Vitamin C, to create an effective flu-fighting remedy (C). The information then expands on the broader context by stating that this combination also supports a healthy immune system (D) . Finally, the sequence concludes by specifying a potential consequence of insufficient vitamin C, noting that individuals with low levels are at a greater risk of infection (A). This order ensures a coherent flow, moving from the significance of a specific vitamin to a more comprehensive view of immune system support.

Therefore, the correct answer would be: " BCDA."