Answer: Avoid drinking unpasteurized juice
Step-by-step explanation:
To protect Todd, he should avoid drinking unpasteurized juice. We should note that when a juice is pasteurized, it simply means that it's been heated, which then helps in killing harmful bacterias along the way.
Unpasteurized juice on the other hand contains harmful viruses and bacterias like cryptosporidium parasites and since Todd is at increased risk of infection because of poor liver function, this is bad for his liver and he should be advised not to drink it.