A child presents with sepsis. Bacteria isolated showed beta hemolysis on blood agar, resistance to bacitracin, and a positive CAMP test. The most probable organism causing infection is -
Points favoring to S. agalactiae:

Septicemia in a child
β hemolysis on blood agar
Resistant to bacitracin and a positive CAMP test

S. pyogenes: sensitive to bacitracin and CAMP test is negative.
Ref: Apurba Sastry’s Essentials of Medical Microbiology 1/e p229, Ananthanarayan 9/e p216, 8/e p207
S. Pyogenes
S. Agalacitae
Enterococcus
S. Pneumoniae