Immunogenicity and Safety of Meningococcal Groups A and C and Haemophilus b Conjugate Vaccine in Infants 2 to 5 Months of Age

To evaluate Immunogenicity and Safety of Adjuvant and Adjuvant-Free Meningococcal Groups A and C and Haemophilus b Conjugate Vaccine in Infants 2 to 5 Months of Age. Primary objective: * To demonstrate the non-inferiority of the antibody responses to meningococcal serogroups A, C and Haemophilus influenzae type b following the administration of adjuvant-free MenAC-Hib conjugate vaccine compared to those observed following the administration of adjuvant MenAC-Hib conjugate vaccine. * To describe the safety profile of adjuvant-free MenAC-Hib conjugate vaccine compared to that of adjuvant MenAC-Hib conjugate vaccine. Secondary objective: •To compare the antibody level of meningococcal serogroups A, C and Haemophilus influenzae type b following the administration of adjuvant-free MenAC-Hib conjugate vaccine to those observed following the administration of adjuvant MenAC-Hib conjugate vaccine.