As long as I am willing to put in time and effort, I will receive the results I desire. I will make a 173+ on the LSATs this September.

Somehow the cats confused me more than the kingdoms... this will take longer than I originally thought.

It seems, from your explanation, you might've got it confused for the conjunctions which is being infected and being infected for a week. Not, being infected, then being infected for a week and having antibodies. This might've caused the switch up with the necessary and sufficient conditions.

The sentence should be separated like this for the exercise:

"Anyone infected by the virus will, after a week,"

"produce antibodies to fight the virus."

For me, I could immediately tell from the indicator "Anyone" as "any" is one of out Group 1 sufficient condition indicators.

But I also thought it out as:

"Is the sentence telling me that someone having the antibodies means they've been infected for a week?"

No, they could get antibodies from anywhere, I just know if they've been infected for a week then they'll definitely produce the antibodies.

Yes, I think so, but we have to remember that just because B has happened, that doesn't allow us to conclude C has or hasn't.