Final answer:
The pregnant client is at risk for metabolic acidosis due to significant weight loss resulting from severe morning sickness, not dehydration, since the client does not exhibit symptoms of dehydration.
Step-by-step explanation:
The client described in the Nurses' Notes is at risk for experiencing metabolic acidosis due to the client's weight loss. The significant weight loss of 6.8 kg (15 lb) over the past month, along with persistent nausea and difficulty eating, suggests the client may be experiencing severe morning sickness, leading to inadequate nutrition and potential electrolyte imbalances that could result in metabolic acidosis. Given that the client does not report symptoms such as dry mucus membranes, which might indicate dehydration, weight loss stands out as the primary concern related to metabolic acidosis risk.