Practice NBME offered by school

I took a practice CBSE offered at my school and jotted down questions/concepts I was unfamiliar with. Any help with these questions (and more to come) is appreciated.

Pregnant woman with pain in her breast and has a crack in the skin of her nipple and says she feels weak. What is the causal organism?
S. aureus
S. epidermidis
S. agalactiae
S. bovis
S. pyogenes

6wk infant presents with bilious vomiting. Diagnosis?
Hiatal hernia
annular pancraes
Meckel's diverticulum
Pyloric stenosis
TE fistula...

Practice NBME offered by school