Sal monella infection is most commonly caused by-

Ans. is 4a & b' i.e., Infected water & Infected vegetable Transmission of salmonella tvphio Typhoid fever is transmitted via the faecal-oral route or urine-oral routes. This may take place directly through soiled hands contaminated with faeces or urine of cases or carriers, or indirectly by the ingestion of contaminated water, milk and/or food, or through files.Dynamics of typhoid fever transmission