Most of these I would advise you not to handle food with, but the most seriousness of these diseases is Typhoid Fever. Typhoid Fever is obtained by food an infectious person handles. The answer is C.
Common cold is the illness in which a person should not work with food or food preparation area because the common cold is an infectious disease caused by viruses which he can easily spread around the people by contaminating food with the virus.
Hepatitis A, shigellosis, and typhoid spread mainly through the fecal-oral route so in these disease good personal hygiene prevents the disease to transmit to others but the common cold can be transferred easily by infected person because the virus can be spread through air by water droplets released by infected person in the preparation area.
Therefore the correct answer is d. The common cold.
