F.2 Mathematics

Suppose there are 4 houses : House A,B,C and D
For answer (A):
the letters can be distributed as follows:
A:3 B:3 C:1 D:1
So , C and D have only one letter .
(A) is wrong.
For Answer (B):
the letters can be distributed as follows:
A:2 B:2 C:2 D:2
which shows that no houses received at leat three letters.
(B) is wrong.
For answer (C) ,
take the example in (A) as reference . A and B can have 3 letters .
(C) is wrong.
For answer (D) ,
If one of the houses (for example , A) has received more than five letters .i.e. A has six letters received.
A:6 B:1 C:1 D:0
which contradicts that at least one letter delievered at each house.
So, [No house received more than five letters] is true!