From an old niche [recess] we have made a cupboard; and dan old cupboard in the wall with stones and rubbish we have cleaned; we have stopped the holes in the wall, pulled out old nails, put in new boards and painted it.

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which identifies the contact clue that is most in determining the meaning of the word niche

a) old cupboard in the wall
b) stopped the holes
c) [ recess]
d painted it

The contact clue that is most helpful in determining the meaning of the word NICHE is [recess].

Explanation:

The word recess can have different meaning depending on the context, in this sentence the word recess uses the meaning of hole or cavity, the meaning can be deduced also for the preposition "in" when they mention the old cupboard "in" the wall, which means it was inside it like a cavity not "on" it as a piece of furniture.

i dont know if your mis-read or whatever but that says 30 points also. its not so very surprising knowing that the words he spoke was english, the aspect of his "language" i'd say is pretty rare and is very unique to pronounce.