I took our dog Jack ... ( he 's a long haired chihuahua ... very cute and very loved ) ... .. to the vet last week because he was coughing , I thought it was a cold or some minor thing that they could diagnose , treat and all would be well . It turns out that his big heart is too big and pressing against his esophagus , he also had fluid in his lungs , Jack is 8 . The vet gave me an antibiotic and a diuretic and asked us to come back in 10 days .
Why is the narrator so worried about Jack ?
Pick the best answer from the following options:
- Jack has an enlarged heart .
 - Jack has run away .
 - Jack has an issue with attacking others .
 - Jack has an issue with biting .


Jack has an enlarged heart .