To obtain good bonding in brick masonry A. First class bricks are used B. Vertical joints in alternate courses are kept in plumb line C. Bats are used where necessary D. All the above

The correct answer is D. All of the above are necessary to obtain good bonding in brick masonry.

First class bricks are used because they are strong and durable. They should be free of cracks, chips, and other defects.

Vertical joints in alternate courses are kept in plumb line to ensure that the wall is straight and vertical.

Bats are used where necessary to fill in the space between the bricks. They should be cut to the correct size and shape to ensure a good fit.

All of these factors are important for obtaining good bonding in brick masonry. If any of them are not done correctly, the wall may be weak and unstable.