Answer:
Presence of Aschoff's bodies
Explanation:
Rheumatic fever is developed by the strep throat problem which was not cured properly and some bacteria left in bodies which are streptococcus bacteria.
Rheumatic fever effect heart functionality and it makes the heart working weak.
The Rheumatic fever can be observed by the swelling in joints, heart checkup, body movement dysfunctional, throat checkup.