A forensic anthropologist examines the upper arm bones of a single individual. She notes that the diameter (thickness) of the left arm bone is significantly larger than that of the right arm bone. From this she can infer that:

The use of left arm is more compared to right hand

Explanation:

In the given question, the anthropologist when examines the left and right arm he found that the left arm is thicker than the right arm.

The more thickness of the left arm signifies that the person uses his left arm for the muscular work as the more use of hand increases the deposition of the calcium phosphate and sulfate in bones along with other material which increases the thickness for the bones and increases the strength.

Thus, The use of the left arm is more compared to the right hand is correct.

i think the answer is b.