1. 

1. A3P means A is the mother of P

2. A4P means A is the brother of P

3. A9P means A is the husband of P

4. A5P means A is the daughter of P

Which of the following means that K is the mother-in-law of M?
A. M9N3K4J
B. M9N5K3J
C. K5J9M3N
D. K3J9N4M

Answer: Option B

Explanation:

M9N ? M is the husband of N

N5K ? N is the daughter of K

Hence, ? M is the son-in-law of K

K3J ? K is the mother of J

Hence, ? K is a lady

Hence, ? K is the mother-in-law of M.