A 25 year old woman had premature rupture of membranes and delivered a male child who became lethargic and apneic on the 1st day of birth and went into shock.The mother had a previous history of abortion 1 year back.On vaginal swab culture growth of Beta-haemolytic colonies on blood agar was found.On staining these were found to be gram positive cocci.Which of the following is the most likely etiological agent?

• A. Strptococcus agalactiae
• B. Strptococcus pyogenes
• C. Enterococcus faecum
• D. Peptostreptococci