3. In a criminal investigation, five suspects have been arrested. They all make one statement:

Eva: "We are all innocent."

Fatima: "Exactly one of us is innocent."

Kees: "Exactly one of us is guilty."

Manon: "At least two of us are innocent."

Mustafa: "At least two of us are guilty."

It turns out that only the guilty ones lie and the innocent ones tell the truth. How many guilty suspects are there among these five?
A) 1
B) 2
C) 3
D) 4
E) 5
A3. C) 3 At most one of the statements made by Eva, Fatima, and Kees can be true. Therefore, at least two of them are lying and are guilty. From this, we can already conclude that Eva and Kees are lying and thus guilty. Therefore, Mustafa is telling the truth and is innocent.

Fatima cannot be telling the truth, because then she and Mustafa would both be innocent, which contradicts her own statement. Therefore, Fatima is guilty.

Manon cannot be lying, because then she would be guilty and Mustafa would be the only innocent person. But then Fatima would indeed be telling the truth.

We conclude that Manon and Mustafa are the only innocent ones. This also matches their own statements and the lies of the other three.