Step 1: Reference story.
This is based on the humorous story "A Triumph of Surgery" by James Herriot. Tricki is an overfed pet dog, owned by Mrs. Pumphrey.
Step 2: Tricki’s health issue.
Tricki was not suffering from any serious illness. His real problem was overfeeding and pampering by Mrs. Pumphrey. Due to excess rich food and lack of exercise, he had become obese and started vomiting.
Step 3: Option Analysis.
(A) Malaria — Incorrect, not mentioned in the story.
(B) Malnutrition — Opposite of Tricki’s issue.
(C) Fever — Not relevant.
(D) Vomiting because of excess of food — Correct, as per vet's diagnosis.
Step 4: Conclusion.
Tricki’s actual problem was not a disease, but a lifestyle issue caused by overfeeding.