Question

adapted from centers for disease control, food-borne illness, faqs
1 we live in a microbial world, and there are many opportunities for food to become contaminated as it is produced and prepared. many food-borne microbes are present in healthy animals (usually in their intestines) raised for food. meat and poultry carcasses can become contaminated during slaughter by contact with small amounts of intestinal contents. similarly, fresh fruits and vegetables can be contaminated if they are washed or irrigated with water that is contaminated with animal manure or human sewage. some types of salmonella can infect a hen’s ovary so that the internal contents of a normal looking egg can be contaminated even before the shell is formed.
2 later in food processing other food-borne microbes can be introduced from infected humans who handle the food, or by cross - contamination from some other raw agricultural product. in the kitchen, microbes can be transferred from one food to another food by using the same knife, cutting board or other utensil to prepare both without washing the surface or utensil in between. a food that is fully cooked can become recontaminated if it touches other raw foods or drippings from raw foods that contain pathogens.
3 the way that food is handled after it is contaminated can also make a difference in whether or not an outbreak occurs. many bacterial microbes need to multiply to a larger number before enough are present in food to cause disease. given warm moist conditions and an ample supply of nutrients, one bacterium that reproduces by dividing itself every half hour can produce 12 million progeny in 12 hours. as a result, lightly

• which best expresses the main idea of this passage?

a food contamination is caused by microbial infection.
b refrigerating food can have avoid food contamination.
c foods can become contaminated in many different ways.
d cooking food thoroughly can help prevent contamination.

• which line from the passage best expresses its main idea?

a unpasteurized fruit juice can also be contaminated, if there are pathogens in or on the fruit that is used to make it.
b we live in a microbial world, and there are many opportunities for food to become contaminated as it is produced and prepared.
c recently a number of outbreaks have been traced to fresh fruits and vegetables that were processed under less than sanitary conditions.

Explanation:

First Question (Main Idea of the Passage)

• Option A focuses only on microbial infection as a cause, but the passage lists multiple causes (e.g., contact during slaughter, contaminated water, cross - contamination, etc.). So A is incorrect.
• Option B only mentions refrigeration, which is not the main focus of the passage. The passage is about how food becomes contaminated, not just about prevention via refrigeration. So B is incorrect.
• Option C: The passage describes various ways food can be contaminated (during production, preparation, processing, handling after contamination). This option accurately captures the main idea.
• Option D focuses on cooking as a prevention method, but the passage is about how contamination occurs, not just prevention. So D is incorrect.

• Option A is about unpasteurized fruit juice contamination, which is a specific example, not the main idea.
• Option B: "We live in a microbial world, and there are many opportunities for food to become contaminated as it is produced and prepared" introduces the main topic of the passage - the multiple ways food can be contaminated during production and preparation, and this is supported by the rest of the passage.
• Option C is about a specific outbreak related to fresh fruits and vegetables, which is a detail, not the main idea.

Answer:

C. Foods can become contaminated in many different ways.

Second Question (Line Expressing Main Idea)