The surface area of a cuboid is

The surface area of a cuboid is calculated by summing up the areas of all six rectangular faces. A cuboid has three pairs of opposite faces, and the area of each pair is as follows:
1. Two faces with area lb (length × breadth),
2. Two faces with area bh (breadth × height),
3. Two faces with area lh (length × height).

Thus, the total surface area is given by:
Surface Area = 2(lb) + 2(bh) + 2(lh)

Factoring out the common factor of 2, we get:
Surface Area = 2(lb + bh + lh)

This matches option a) 2(lb + bh + lh), which is the correct formula for the surface area of a cuboid.

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