A 1-month-old infant underwent a spinal tap to rule out bacterial meningitis. The CSF was cloudy, and the smear showed many pus cells and short gram-positive rods. After 18 hours, many colonies appeared on blood agar that resembled Streptococcus agalactiae (Group B Beta Strep) or L. monocytogenes. Which of the following preliminary tests should be performed on the colonies to best differentiate L. monocytogenes from Streptococcus agalactiae?
A. Motility (25°C) and catalase
B. PYR and bacitracin
C. Oxidase and glucose
D. Coagulase and catalase