Amoebic dysentery is caused by the parasite Entamoeba histolytica. This single-celled amoeba is transmitted through contaminated food or water, particularly in areas with poor sanitation. Once inside the body, the amoeba infects the large intestine and causes symptoms such as severe diarrhea, abdominal pain, and bloating.

Option 2, Salmonella typhi, is not the correct answer because it causes typhoid fever, not amoebic dysentery.

Option 3, E. coli, is a bacteria that can cause food poisoning, but it is not the primary cause of amoebic dysentery.

Option 4, Streptococcus pyogenes, is a bacteria that causes strep throat and certain skin infections, but it is not associated with amoebic dysentery.

Thus, the correct answer is option 1, Entamoeba histolytica.