Final answer:
An older client with a diet consisting largely of crackers, cookies, cereals, and tea is at risk for protein-calorie malnutrition, due to lacking balanced nutrition essential for maintaining health.
Step-by-step explanation:
An older client who lives alone and consumes mainly crackers, cookies, sweetened cereals, and tea, is at risk for protein-calorie malnutrition. This condition occurs due to inadequate intake of protein and calories which are essential for maintaining muscle mass and body functions. The symptoms of malnutrition include muscle atrophy, reduced immune response, and overall weakness, and it often affects the elderly and those with chronic diseases. Considering the client's diet lacks significant sources of protein and other nutrients, they do not receive the balanced nutrition required for good health, contributing to the risk of malnutrition.