Which contain(s) bacteria in the cardiac lesions?

Acute rheumatic heart disease (A) can contain bacteria in the cardiac lesions. This condition is a complication of rheumatic fever, which is caused by a streptococcal infection. In contrast, recurrent rheumatic heart disease (B) generally involves chronic damage from prior rheumatic fever and does not typically contain active bacteria in the lesions. Therefore, the correct answer is:

A. acute rheumatic heart disease