Typhoid fever in humans is caused by:
- Entamoeba histolytica
- Salmonella typhi
- Plasmodium vivax
- Streptococcus pneumoniae
Show answer and solution
Correct answer: B. Salmonella typhi
**Typhoid** is caused by **Salmonella typhi** — enters small intestine via contaminated food/water, migrates via blood.
**Symptoms:** sustained 39–40°C fever, weakness, stomach pain, constipation.
Confirmed by **Widal test**.