The nominal thickness of one brick wall in mm, is A. 90 mm B. 150 mm C. 190 mm D. 200 mm

The correct answer is B. 150 mm.

A brick wall is a masonry wall made of bricks. Bricks are typically rectangular in shape and have a nominal thickness of 150 mm. The nominal thickness of a brick wall is the thickness of the individual bricks that make up the wall. The actual thickness of a brick wall may vary depending on the type of bricks used, the mortar used to join the bricks, and the method of construction.

Option A is incorrect because the nominal thickness of a brick is 150 mm, not 90 mm.

Option C is incorrect because the nominal thickness of a brick is 150 mm, not 190 mm.

Option D is incorrect because the nominal thickness of a brick is 150 mm, not 200 mm.