Concept:
The word emaciated describes a person who is extremely thin and weak, often because of illness, starvation, or severe lack of nutrition.
Step 1: Understand the context.
The sentence mentions a patient arriving in a wheelchair, indicating poor health and physical weakness.
Step 2: Determine the meaning of emaciated.
\[
\text{Emaciated} = \text{abnormally thin, skeletal, wasted}
\]
Step 3: Compare the options.
• Active -- energetic and healthy.
• Bony -- very thin with bones clearly visible.
• Healthy -- physically fit.
• Sturdy -- strong and robust.
Step 4: Select the synonym.
The closest synonym of emaciated is bony.
\[
\boxed{\text{Bony}}
\]