Which among the following is the etiological agent of 'pneumonia alba'?

Pneumonia alba is seen in congenital syphilis which is caused by Treponema pallidum. Neonatal or infantile congenital syphilis, with lesions containing numerous spirochetes and resembling those of early syphilis in the adult, ie, desquamative skin rashes and ulcerating patches on mucous membranes. Osteochondritis and perichondritis have severe effects on growing bone and cailage--especially the nose, causing nasal bridge collapse (saddle nose), and tibia (sabre shins). Liver involvement leads to hepatic fibrosis and pulmonary involvement to fibrosis and inflammation of the lungs (pneumonia alba). Ref: Chandrasoma P., Taylor C.R. (1998). Chapter 54. Sexually Transmitted Infections. In P. Chandrasoma, C.R. Taylor (Eds), Concise Pathology, 3e.